I folowed your instruction but I have an issue with with flashing the original SPL, it stop on 97%, after a while i gave up and after rebooting the phone the SPL reads 1.25.000 then flash the t-mobile 6.5ROM and it went through and my phone is happy. me too.
I have confirmed this. You can not just run Jockys RomUpdateUtility.exe though, it will not work. You must run the auto.bat from within winmo. If you are stuck at the tri color then just reflash any spl (jocky) using the romupdateutility and it should boot. Then run the auto.bat. It will freeze at 97%, remove battery and USB, insert battery. You will see tri color with error code. Run T-mobile update and it should work.
EDIT:
Ok so to recap
1) Extract Jockeys HARD SPL and T-Mobile's 6.5 Rom into seperate folders.
2) Delete any .nbh files from Jockys directory
3) Copy the SPL.nbh from T-mobile directory into Jockeys
4) Run jockys auto.bat with your phone started up in windows mobile.
5) It will freeze at 97%, wait a minute and remove battery and usb.
6) Re-insert battery and power on. You will see tri color with error code.
7) Run the ROMUpdateUtility.exe from T-mobile 6.5 directory.
If you are stuck at tri color and cant boot into windows mobile to run auto.bat:
1) Follow steps 1 - 3 above.
2) run the ROMUpdateUtility.exe in Jockys directory. It will complete but will not change the SPL for some reason and boot into windows mobile.
3) Continue from step 4 above.