I was able to roll back my phone from 2.2 to 2.1 back in august, I had root, recently my phone was unintentionally updated to the stock 2.2 baseband version 2.15.00.07.28 kernal version 188.8.131.52-g746f4f0 build number 3.26.651.6 CL218634 software number 3.26.651.6 browser version webkit 3.1 PRI Version 1.40_003 PRL Version 60671. I have tried about six time to repeat the roll back to 2.1 process to no avail to regain root, as near as I can tell when I'm in hboot and the PC36IMG.zip is flashing I get a message that says PC3DIAG.zip wrong or no image. After the reboot I am still in 2.2 I have done a lot of searching and seem to be the only person having this issue. If there are any big brains out there that might have the answer. You can have my first born. Thanks.