[MDA, XDA, 1010 Software Upgrading] ebswift:
Hi All,

After a LOT of reading and mucking about, I've been able to update my ROM, get full use of GPRS and revert back to the manufacturer's ROM. There are a number of instructions, some of which are pretty dangerous. The following forum topic is the invaluable guide you need to read if you wish to revert back from a T-Mobile installation :

http://xda-developers.com/forum/viewtopic.php?t=3274

The place to get your ROM's is http://www.yorch.net, from the ROM Kitchen. Use the XDA Tools from the above forum link to burn ROM's you download from Yorch's onto your beloved XDA (use the .nb1 format, NOT the .exe method and burn using XDA Tools through your USB cradle).

I happen to have the 5.17 Wallaby bootloader which means that it will not let you simply whack in an SD card with a new O/S and burn off a backup ROM, it won't happen. Don't try to upgrade your Wallaby bootloader. The safest method is to use the Wallaby bootloader patch which can be downloaded from a link at the top of the forum topic link I posted above. That allows you to do a simple O/S restore from your SD card, providing you have an SD reader which presents your SD card as a new drive on your computer. The instructions are simple, just use xdrit as per the instructions in the forum topic link above.

So, from my experience I backed up my original ROM using XDA Tools and stored it on my hard disk in .nb1 format. I then downloaded the .nb1 for 4.00.16 and installed it using XDA Tools without a hitch. Everything worked fine, but I wasn't comfortable until I knew I could revert back to my original ROM. So my next step was to write the Wallaby Patch tool onto my SD card using xdrit using the instructions as laid out in the forum topic link above (take note, use the 1K header option in xdrit). The SD card reader I used was an X-Drive that you normally use for digital camera style stuff. Once written, I put the SD card in the XDA and did the bootloader boot (hold the power button whilst pressing the reset button), and was then given the option to press the Action key to go into the diagnostic mode which is where the patch program resides.

I then took the SD card out, leaving the diagnostic screen still open, put the card back into the X-Drive, formatted it using default options in Windows XP, then wrote the ROM backup I had (you can use any ROM here) onto the SD using xdrit, selecting the 3.5K header option (because we are still using Wallaby 5.17 regardless of patching). The last major step was to place the SD card back into the XDA and select Restore SD and accepted the risk notices. The restore appeared to go fine, but at the end it said Incorrect CRC. That in itself is a worry, but I had at least restored to a point where I could burn whatever ROM I like using the simple XDA Tools method, which is exactly what I did after reviewing the connection info (once more), going to 4.00.05.

Before I originally went to 4.00.16 I recorded all my connection details, including proxy info. When I went to 4.00.16 and re-entered all the gprs info, I found that the internet worked, but MSN Messenger would not connect, stating that the proxy info was incorrect - even though the values were exactly as originally setup. That was one major reason for wanting to go to another ROM. However when I ultimately got 4.00.05 on, I kept getting exactly the same error message with MSN Messenger. The answer came from a hint in another forum topic where someone (with AT&T I think it was) said not to put anything in the proxy info. That did the trick. Un-ticking the proxy option allowed the internet and MSN Messenger to work perfectly.

For Telstra GPRS (I think this is universal) the access point name is : telstra.wap.mnc001.mcc505.gprs

GPRS Authentication method is PAP authentication.

Hopefully this info might help someone out there, because I spent close on 8 hours sweating over trying to get my original ROM back up and running.