I don’t know why the decision was made, and it is a surprise decision, to me at least, because it appears so destructive. As many have commented already, this is a big win for Microsoft and a capitulation for Nokia. They have done what they said they wished to avoid, becoming just another ODM shifting boxes; Nokia instead of fighting to maintain their ecosystem have ceded it in their deal with Microsoft: the Ovi Store is being rolled into the Windows Marketplace; Qt a large selling point up to now for its write once, run anywhere potential has been diminished by the decision to not bring it to Windows Phone; and finally, Windows Phone is not even a Nokia exclusive. The fear of not being able to differentiate among all the Android vendors, is just as applicable here.

Without explicitly saying it, we are seeing the probable end of any future for MeeGo on handsets from Nokia, with only plans for a MeeGo ‘device’ sometime later this year; I cannot see how Microsoft would allow Nokia to put out a competing handset in the wording of the deal, so I believe it will be another experimental internet device.

As for Symbian, any reason to buy the quite accomplished hardware-wise Nokia Symbian handsets has been destroyed, out of fear for a lack of long-term updates and developer support. For example, personally I find the Nokia N8 a compelling device technologically. It has advanced hardware such as Bluetooth 3, USB OTG, a 12 Megapixel Carl Zeiss camera with xenon flash, 802.11n wireless and HDMI out. Its design is an improvement over its forerunners, but despite the much improved Symbian over the version in my current phone (Nokia N82) its still off putting, because I know and have known that despite this announcement, Symbian had a limited future, especially in the high-end — such was said a year ago by Nokia. We all expected MeeGo to be taking over around now, and it certainly had strong potential, and good partnerships to back it up, fitting in as well to a cogent broader strategy to maximise distribution on multiple devices and increase attractiveness and ease for developers.

In contrast, the situation painted at the Nokia capital markets meeting is that of fragmentation and further delay. Again, as others have rightly pointed out, an uncertain future for MeeGo, a limited one for Symbian and a delayed one for Windows Phone — with devices not expected in number till 2012 — where is the incentive for either customer or developer? I am not denying that Nokia may come out with compelling handsets running Microsoft’s mobile operating system, in a year or so, but there has been massive betrayal of expectant end-users and especially developers; not to mention partners such as Intel, and the Linux Foundation.

Now for my brutal opinion. I believe that Stephen Elop has done this for ideological reasons, increasing the partnership with Microsoft to an unprecedented degree. Nokia’s fate is now largely tied to Microsoft, which is an unenviable situation given Microsoft’s history of bad relations with partners; Microsoft’s fate is nowhere tied to Nokia, at all. It’s simply a poor deal, from what we’ve seen so far. I do not believe it will be successful in coming anywhere near the dominant market leaders. I think that Nokia was seriously innovating in openness, and that it is the leveraging of open source technologies that will define the future of mobile technology. I don’t know the state of MeeGo but surely it would have been less effort to accelerate MeeGo’s development than to change in such a startling and comprehensive manner?

I recently upgraded from Fedora 13, to the new Fedora 14 release. Despite keeping my old "/home" directory, there was a lot of reinstalling and tweaking that I had to go through. With my laptop I make use of battery charging thresholds, which are good for preserving the longevity of your battery life, and stop it being prematurely depleted. The way battery charging thresholds work, are that they inhibit charging when the AC adaptor is connected, until the battery level is above and below a certain percentage. I tend to use the levels, 20% and 80%, so that the battery doesn’t begin charging until the battery level is below 20%, and when this occurs it stops charging at 80% of the total battery capacity; as I have mentioned, this prevents unnecessary wear to the battery. It is especially useful if your laptop is generally always connected to the AC adaptor, apart from the odd rare occasion. Because then you can set the battery to stay at a safe, 40% or so, which would keep it from being worn down, despite being installed in the laptop, with the AC adaptor attached.

Battery charging thresholds are a rather advanced feature, and it’s not in-built into the Linux kernel, so far as I know. There is however a kernel module for Thinkpads called tp_smapi. This module provides an interface for advanced features, such as battery charging thresholds, among other things. Now I will move on to explaining how to install the tp_smapi kernel module.

You can build tp_smapi from source, in which case here’s the link to some more detailed instructions and steps to follow on ThinkWiki. However, I find that this still does require a modecombe of concious effort on my part to keep tp_smapi up to date and working with my current kernel version (which gets updated a lot more frequently than tp_smapi itself.) So, the solution is to use a prepackaged kernel module, that can automatically rebuild itself. This is called an akmod or automatic kernel module. Thankfully, somebody smarter than me has already built just such a package for use with Fedora. You can download it from here, you’re looking for the package titled akmod-tp_smapi-0.40-1.fc11.i686.rpm.

So I’m presuming that you’ve downloaded it to your “/home/YourUsernameHere/Downloads” directory, in which case we need to open a terminal and switch to that directory:

cd /Downloads

The next step is to install the akmod. Probably the best way to do this is a local install with YUM. You need to be root in order to install this program, so use “sudo” if you’ve set it up, if not you can use “su -c” which I have used below (so you can quickly copy and paste it):

su -c 'yum localinstall akmod-tp_smapi-0.40-1.fc11.i686.rpm --nogpgcheck'

Now read the on screen instructions to confirm that it has installed okay.

Before tp_smapi will work you need to reboot your computer. Instead of watching the pretty Fedora startup screen (the silhouette of the Fedora logo slowly filling up with white), press the Escape key on your keyboard, to show the log of what’s happening on boot. You’ll see an entry for tp_smapi, being built. If it’s successful you’ll see a green “[Ok]” next to the entry. If not, you’ll also be warned at boot time, with an orange caution-triangle, showing boot time errors, before and after you log in.

So now, hopefully it has built successfully and should work. However, you have to manually load the new kernel module. To do this, again, become root user and execute the following command in a terminal:

su -c 'modprobe tp_smapi'

To verify this has worked I then (still as root user, and you have to explicitly type “su” and the root password) execute a command to show me the battery charging thresholds, as follows:

cat /sys/devices/platform/smapi/BAT0/*_charge_thresh

This should display two numbers, on above the other, in the terminal. The first, and top one is the thresholds to start charging at, the one below it, the last one, is the level at which the battery stops charging. It may be a good idea, to note down the above command, as it’s quite useful if you want to remember how to use these battery charging thresholds.

The final part of setting up the akmod_tp-smapi is to make sure that it is loaded _automatically_ for you, at boot time, so you don’t have to execute “modprobe tp_smapi” yourself, manually, every time you reboot. To do this, you need to be root, and execute the following command:

echo modprobe tp_smapi > /etc/rc.d/rc.local

Now if you reboot your laptop and then try the command to show you the battery charging thresholds, as root (cat /sys/devices/platform/smapi/BAT0/*_charge_thresh), it should just work for you.

A final point to note are the two commands below (you, again, must switch to root with “su“):

echo 20 > /sys/devices/platform/smapi/BAT0/start_charge_thresh

echo 80 > /sys/devices/platform/smapi/BAT0/stop_charge_thresh

As I have mentioned before, these are the two battery charging thresholds that I use. The top one, as the end of the command suggests, is the start threshold, and the second is the stop charging threshold. Execute these commands, with your own numbers after “echo“, and it’ll set those values for you. If you put the two commands on to one line, and separate them with a semi-colon, like so:

echo 20 > /sys/devices/platform/smapi/BAT0/start_charge_thresh; echo 80 > /sys/devices/platform/smapi/BAT0/stop_charge_thresh

Then it will execute the two commands at the same time, to avoid having to copy and paste twice. Remember, use the following command to check the charging levels:

cat /sys/devices/platform/smapi/BAT0/*_charge_thresh

I was a bit concerned when moving from the wholly IBM made T41p to the Lenovo manufactured T61 there was a difference, and that is worrying when holding a very much loved brand in its hands. The T61 made a number of compromises from the old ‘p’ performance model. Going from a 4:3 aspect ratio and screen resolution of 1400×1050, to a widescreen 16:10 and resolution of 1280×800 is a big change, you lose that vertical screen real-estate and greater resolution in general but on the upside the newer LCD was brighter.

Moving to the T400, I again noticed a considerable improvement in the brightness of the LCD display and at this point had become used to the more restricted resolution, if anything it saved my eyes.

Another thing about the older Thinkpads were they used to get very hot, probably contributed to by the performance discrete-graphics which were lacking in my T61. The T400 on the other hand has ‘switchable graphics’, both integrated and discrete graphics chipsets that can be selected in the BIOS as well as at runtime if there is OS support (no there is currently no Linux support for this). What struck me was that the T400 was even cooler than the T61 despite having both graphics chipsets inside it. This can be attributed to the refinement in processor production, moving to smaller manufacturing processes means a smaller thermal output, this coupled with an improvement in fan and cooling technology — is visible if you look at the heatsinks behind the fan grilles, they’re now copper and not aluminum — there were also improvements made to the design to make them more efficient. I should note that under Linux the laptop is cooler in most situations than under Windows, at least for the integrated graphics. I talk at length about these things because they’re noticeable factors and are quite important if you use a machine day in day out.

A smaller difference is the improvement in weight and size which although slight is noticeable and much welcomed.

Of course with increased specifications there is increased power but what makes this even more amazing is that the power is so much greater and yet the heat and weight are the same if not lower. Moving up to an Intel Core2 Duo instead of just the Intel Core does make a difference, perhaps the faster DDR3 RAM also plays a part in this; now that I have upgraded my RAM to 4GB I find using swap space almost a thing of the past.

I would always recommend getting a desktop-speed, that is 7200RPM, hard disk drive as this is the bottleneck in most systems I just swapped over my T61′s HDD, only having to remove one screw to gain access to it (it is placed on a caddy with shock absorbers).

These details bring me to another strength of Thinkpads in general customisability and support. One cannot argue with a three-year on site warranty, that’s next day support including parts and labour, brilliant. With the help of ThinkWiki and the Thinkpads.com forum as a guide, one has enough information to maintain this system for a long time. Thinkpads are built to facilitate easy access and modularity, they publish a hardware specification called the Hardware Maintenance Manual (HMM) (link for the T400 HMM) that shows you step-by-step, with exploded view diagrams for help, how to assemble and disassemble your individual Thinkpad model. Things that would normally be a chore to replace if they went wrong on other manufacturers laptops, like disc drives, are simple as they are modularised in the form of the UltraBay, a removable disc drive. The HDD as I have mentioned is also on an easy access and removal caddy and the RAM is not very hard at all to replace. What’s more many of these more minor things such as replacing the RAM do not void your warranty and if something goes wrong, sometimes Lenovo will merely send out the part, so well documented and easy is the process of disassembly, it’s a real ‘feature’ for me.

The keyboard remains one of the chief components that bring people to the Thinkpad line, it is world renowned and still holds up well to this reputation. If you go into a laptop shop, just press down firmly on the keys in the middle of the keyboard, watch it bend and flex, sometimes quite a lot. Thinkpads don’t really suffer from this and typing on the T400 is a joy. Night typing is helped with the continued presence of the ThinkLight, an LED that lights up the keyboard to an extent (Fn+Page Up).

The speakers are no longer located on the base, facing downwards towards the user but are on the sides of the keyboard, they’re noticeably louder than in previous models, especially than the T41p.

Battery life is very good, much improved over the T61 generation despite only possessing a 4-cell battery, using the Windows-only Lenovo BatteryStretch technology I could get 4 hours of battery time, running under reduced conditions however. There are 4, 6 and 9-cell batteries available which again, is not something you see from all manufacturers. Indeed people regularly report reaching over 8 hours on Windows using the 9-cell battery. In Linux equally battery life is good from a hardware perspective, but also I believe there’s been software improvements as it is easy to get the laptop down to around 10W usage which I found very hard to do on older models, this will easily get you 3 hours of battery life at half screen-brightness using the same 4-cell battery,

A brief note regarding Linux support, like most Thinkpads the T400 is well supported on Linux, it’s all documented on the ThinkWiki where you’ll also find user installation notes. There are a couple of things that still as of today do not work perfectly. The audio although working becomes very quiet when adjusted towards the middle of the slider and below and the mute key is not registered by the on-screen display but does mute, as it works in hardware not software [Update: I have found out that this is supposedly fixed in Kernel 2.6.33 and has to do with the BIOS having an ALSA driver, it should now mute at boot and display an OSD]. As I have noted above switchable graphics cannot be fully utilised, switched, at runtime as there is no support in the drivers and may never be, hopefully in a later revision of this technology. The Intel 5300AGN wireless chipset is supported out of the box, within the kernel, and provides a very good range and quality link. The keyboard’s function-key combinations and special keys do work, such as the ThinkLight and even the ones located on the Function keys are supported in large part by ibm-acpi, a kernel package. Integrated graphics provided by Intel work out of the box and work reasonably well, apart from some 3D games where there appears to be some driver peculiarities that cause graphical glitches, the discrete ATI HD3470 is just picking up basic open source 3D support now.

There are a few let-downs when it comes to the T400, not all of them Lenovo’s fault. It would’ve been nice to have a digital video-out in the form of DisplayPort or DVI (which is available on the dock), this was achieved in the thinner and lighter X300 so there was no real reason for the omission here. The only other thing really missing for future-proofness would be USB3 as this already has 802.11n wireless built-in, however that is not Lenovo’s fault and isn’t supported in the chipset.

In conclusion, the Thinkpad T400 is a very well balanced laptop in terms of performance versus weight. It is very powerful and not only uses the latest processor which supports x86-64 as well as advanced virtualisation capabilities but also has a very practical and usable switchable graphics chipset that can provide battery life gains or accelerated graphical power for games or work, when needed; the implementation really is very good falling back to the reliable BIOS switch if there is no OS support, as on Linux. The machine is so powerful in fact that working on this laptop is indeed a step up from my not-too-old desktop computer. I can run games such as Team Fortress 2 and all the productivity software I can shake a fist at, the only issue is really storage, my model only came with an 80GB 5400RPM disk drive but I swapped it out for a 200GB 7200RPM drive, and with greater than 500GB 7200RPM notebook HDDs coming out this isn’t an insurmountable problem. The T400 is more powerful than any of my friends’ machines and yet I got it for cheaper, with the possibility of a longer life in terms of the warranty and the better documentation, spare parts and community support. It has really enabled me to move to this as my sole computer and that is testament, there is not much I cannot do on it.

I hope this hasn’t been a too wishy-washy review, it’s more a general impression to my specific use case than a side-by-side comparison to its competitors. In essence it’s just a great machine, the best Thinkpad I have used so far.

There are some benefits I can see for applications or applets (small applications, usually on the desktop) in there can be tighter integration, with native elements and styling. However I do not believe that this integration cannot be achieved either through a mobile-oriented website or similarly by deploying web based technologies to create these applications, much in the way that Mozilla Firefox add-ons are generally platform agnostic because they use standard open web technologies such as Javascript and CSS.

We’re moving into a time when more and more phones are going to have the ‘full’ internet on them so that at least access can be achieved, whether or not the device is capable of providing the same experience is different, and yet what this phone centric model is creating is fragmentation. Anyone who doesn’t own an iPhone may appear a second-class citizen when it comes to being a user of the internet. This shouldn’t be so, but of course it is Apple’s great success story that they’ve managed to monetise, in many cases, something that should have been and was essentially free, access to the internet.

With a unification in the capability of these devices, greater power, we should be seeing a dissemination of the internet not the same old story of an application only being available on UIQ phones, or Symbian phones and now Apple phones.

What’s wrong with some simple user-agent sniffing to attempt to detect a mobile web browser and give an optimised version? The BBC don’t need an application to provide a very fulfilling and complete experience through their recently revamped mobile website. You can still provide interactivity and in a way that reaches out to the largest userbase.

One cannot really blame Apple in its success, after all it is not forcing these companies to make these applications, they’re only incentivised by the shear mindshare and popularity that Apple has generated. Phones that really are capable of mobile computing, iPhones and N900s to name a few should really be looking to have a universal way of creating applets that will run on any platform — I thought this was what the WRT effort was for. Hopefully the proliferation of the cross-platform QT should alleviate this to an extent but I doubt that it’ll be pushed much by Nokia’s competitors, and why should they. Therefore I would like to see a harmonised effort in this respect. It’s simply better for everyone, the problem is at the moment why would Apple want to change this situation, it benefits them and in fairness I haven’t seen Nokia or any other major manufacturers pursuing a standardised approach to things.

So this is just my thoughts on operating systems for smartphones. I used to be quite biased in favour of Symbian devices (I own an N82 and did a lot of research before hand) but with the N97 and 5800 it’s clear that even with ‘Symbian OS 9.4 5th edition’ it’s like trying to put a square peg in a round hole – it’s not going to work without force and even then it’s misshapen.

As I’ve mentioned in my previous tract about the new Maemo 5 and N900 device from Nokia smartphones are trickling down to the mass-market, unfortunately for Nokia, these new devices most of the time are not running Symbian OS and I am now seeing that even with becoming open source, the Symbian Foundation will not be able to accelerate that pace of innovation quickly enough, to make manufacturers put it on their device. Coming back to the N97, the N97 Mini even, and with the recent 2.0 firmware update, it’s just not fit for purpose. Nokia are fighting a rearguard action against a disruptive innovator, who got to the game ahead of them, or at least innovated a lot faster. I’m talking about Google here, the gorilla in the corner of the room that looks as if it’s about to beat everyone around the head – and Google will, given half the chance. Do no evil my arse. Look at what happened with Mozilla Foundation’s Firefox web browser, Google saw Mozilla making head-way, supported them and then pilfered Ben Goodger, the Lead Developer, along with a list of others and still bankrolls Mozilla to a large degree; now they’re competing head to head with the Chrome browser. My point is that Google’s like the Roman empire, it sees somebody doing something better than them and it copies them, and throws its entire weight behind it – it’s so aggressive. Google maintains this nice and friendly veil of ‘free’, as in beer and even supporting the open source community (see all the people who are on the Google payroll, Google’s summer of code) which is a very seductive principle, but just how altruistic is it as a company? It’s a public company, accountable to share holders, despite its generous track record, a lot of what they have done can be seen to be self motivated, and that isn’t a bad thing for a public company, however one needs to always be aware of it. Android might possibly be dominating the market in terms of new hardware sales, the ones that count. Look at Nokia’s recent historic loss while Apple has made a profit and increased market share, Google’s always making a profit with that huge valuation provided by its stock price.

I’ve briefly mentioned Apple, who must be respected. Where’s Microsoft in this? There was a recent interview with Steve Ballmer on the Engadget Show, where Ballmer mentioned that there are plans to iterate Windows Mobile faster and bring their services together, uniting Zune with Windows Mobile. I’m intent to believe him but at present Windows Mobile doesn’t have either much market share or mind share in the mobile phone space. However they’ve become very successful with the Xbox 360 and the way it has become a portal to subscriptions (Xbox Live Gold) and services based around this (Netflix, Sky Player). I’m sure that the mobile space is where the money is, and this has been born out, as I read in last week’s Guardian Technology supplement regarding mobile computer sales. Why is Microsoft not pushing this more?

Nokia may have had Maemo in the works and on devices, for years; it may be releasing Symbian as open source and it does own QT Software, which is a massive boon if it can really pull this cross-platform interlinkage together quickly enough. However Android is open source, no matter what this thought provoking article says and it has moved at such an incredible pace that it even though it was technically late to the party, it’s the one everybody wants to dance with. It is winning manufacturer contracts all over the place with good reason, it’s slick and it’s far more competitive against the iPhone OS than Symbian 5th Edition is. Maemo wins on all counts of openness but even with the huge advantage of a community, the N900 is one device, and a marginal device just like all the other internet tablets, even though this one version has a phone built in. Until Nokia can start winning real mind share again it won’t win market share.

As for the new Palm Pre and WebOS, it’s just been released over here in the UK and as such a small player I don’t think it’s going to grab much mind share amongst this now crowded market place.

In the time between the N810′s launch, two years ago, and the N900′s announcement the mobile market has changed. This falls largely into two strands: infrastructure and consumer demand. One could easily argue that the concept of an ‘internet tablet’ has always been an oddity, and a very limited market. However what has been made clear by the ascendance of iPhones and Blackberries is that people are demanding internet everywhere. We have also seen further convergence amongst these devices, smartphones are becoming more ubiquitous and so the capabilities of a fully fledged computer are entering our pockets, backed up now, quite often, by an _always on_ style internet connection. The customer’s aversion to long and expensive contract terms has been negated at least in part, they’re according to the sales figures of Blackberries and iPhones among other high-end devices, becoming the norm. So a device in the £500 SIM Free bracket is not an odd price to pay on a two-year or eighteen-month contract plan.

It seems like the natural course then, for Nokia, a phone company, to incorporate cellular capabilities into their internet tablet line. Much has been spoken of by Nokia representatives that the N900 is the enjoining of a computer and a phone, in that order, and not a phone and a computer – putting great emphasis on the ‘full internet experience’ (Flash 9/10, multi-tasking etc) supposedly provided by this device.

Indeed, some have commented that Nokia has been a bit late in adding this function to this line of products and indeed reacting slowly to the increased competition from Apple and RIM’s devices. I can only agree; this is the first of Nokia’s devices to be truly competitive with the iPhone in terms of features and software originality.

I am pleased that Nokia is seemingly putting a lot of money and marketing behind the N900, at least advertising it to developers, which will hopefully in turn carry into consumer’s hands as well. Developer interest certainly seems very active, according to Nokia’s statistics on website hits to http://maemo.org . Let us hope that they follow through with an ad marketing-campaign fit for this prestigous flagship device.

The presentation of the device’s hardware and software is markedly improved over the N810, which in turn was a significant improvement in aesthetics over the plastic-looking N800. The sleek black form-factor, dominated by the 3.5” high resolution touch screen is a step down in physical size from the N810, but what should be considered a measured compromise for a phone sized device. Indeed the size measures favourably with other smartphones, but as I have said previously, the device’s lineage is more from the computer than the phone.

The continued inclusion of a hardware keyboard is welcome to many, as touch screen is still not suitable for all types of fast input (Although it does unfortunately add to the depth of the device). Hopefully the problem of the top-row of the keyboard being too close to the device’s bottom, as on the N810, has been solved. Although small, the keyboard is better than nothing, but with all keyboards one has to try it out for an extended period of time first, in order to form a proper opinion. In general, many have commented that the build quality is good, for example the resistive touch screen is of N97 quality or better.

The real headline feature of the device however, is the inclusion of the latest version of the Maemo operating system, Maemo 5. It is on the whole more user-friendly and more touch-oriented. Indeed, at a glance it is infinitely more presentable, dare I say cool, than earlier iterations of Maemo which look cluttered and unfriendly for a lay user. Maemo 5 includes some unique and re-thought-out usability features like the dashboard and scrolling home screens, which on their own aren’t very unique but the way they have been implemented is a core part of the OS and not just a tacked on gimmick. Home screen widgets aren’t just trivial things, they’ve become important: shortcuts, status updates, news feeds – all provided through the 3G connection.

So why then would a user want the N900 over an iPhone 3GS for instance? Well I must admit that Apple’s cult-like following cannot seemingly be broken. However the N900 continues a recent trend, along with the N97 and N86, of Nokia bringing out more fashionable devices that a normal style-concious user might choose in store. The N900 may be a geek’s device, with function still coming before style, but all that power and flexibility is there if you want it, not imposed upon you; you don’t have to run the x-terminal, you don’t have to delve into all the configuration that you can, you can feel fine just running the default applications (which for the first iteration of Maemo with a phone, is very mature if lacking in a few areas e.g MMS, FM Radio).

What I suggest is that you head on over to YouTube and watch some videos of the interface; it is worlds apart from Symbian OS 9.4 5th Edition which powers the Nokia 5800 and N97, amongst others.

At present I do not have the time nor ability to attempt to fix this, so I do apologise. Download it anyway and give it a go but I’ve had no success myself.

I have now updated Optimoz Tweaks 0.4 to run on Firefox 3.6.

You can get it here. Enjoy.

There’s plenty of information on the history of me unofficially ‘maintaining’ this useful extension, it can be found on the Mozillazine Forums here.

Thanks.

I’ll outline the problem in brief. Say you’re using Google’s email service Gmail and you use “plus addressing” (which is basically username+tag@gmail.com) and you also use mailing-lists. The popular mailing-list server is called mailman and this rejects all emails from email addresses not registered on the list. So if you’ve registered with username+tag@gmail.com but your email client sends new messages out as just username@gmail.com then it gets rejected.

The problem is actually two fold: how do I get Mozilla Thunderbird to compose messages from my “plus addressing” email address and then how do I get Gmail to respect it? Which through testing I find out the hard way, that it doesn’t – the emails still got rejected by the mailing-list.

Setting up ‘multiple identities’ in Thunderbird (I’m using version 3.0):

1. Go to ‘Tools -> Account Settings‘ (on Windows), or go to ‘Edit -> Account Settings‘ (on Linux).
2. In the bottom right-hand corner of the window is a button labelled ‘Multiple Identities‘, click it.
3. Click ‘Add‘ and then fill out ‘Email Address‘ with the email address you need, e.g. username+tag@gmail.com
4. You can then proceed to fill out any other applicable fields. I kept switching back and forth between my other identity, copying verbatim all the settings.
5. Now when composing a new message with ‘Write‘ you can click ‘From‘ and select from either of your identities. Notice that the email addresses should be different. This is what you intended obviously.

Now for some strange  reason, perhaps a good one (Google it, I did) Gmail doesn’t respect you changing your ‘From‘ field. It just reverts it to the account’s email address e.g username@gmail.com . You must do the following to rectify this:

Changing ‘Send Mail As’ in Gmail:

1. Log-in to your Gmail account.
2. Go to ‘Settings‘ at the top right-hand corner of the webpage.
3. And then click the ‘Accounts and Import‘ tab.
4. You are looking at the ‘Send mail as:‘ row, click the button to add the appropriate address e.g. username+tag@gmail.com .

At this point it would be wise to send a test email to one of your mailing-lists in question. You can verify that it went through because you won’t get a rejection email from mailman asking you to contact the administrator. I also verified the email by logging into the mailing-list’s mailman server with my registered username and password and viewing the list’s logs.

I hope this helps someone.

http://kb.mozillazine.org/Multiple_identities_per_e-mail_account

http://mail.google.com/support/bin/answer.py?hl=en-GB&ctx=mail&answer=22370

https://bugzilla.mozilla.org/show_bug.cgi?id=230247

https://bugzilla.mozilla.org/show_bug.cgi?id=264770

http://vafer.org/blog/20060502022752

http://pascal.vanhecke.info/2005/08/31/gmail-sender-header-makes-custom-from-address-useless-for-mailinglists/

http://www.askdavetaylor.com/configure_google_gmail_to_have_a_different_sender.html