[Desire General] gonjeshk:
yes i probably did try any version of unrevoked but it did not work for my rom. here is the error message :

To run a command as administrator (user "root"), use "sudo <command>".

See "man sudo_root" for details.

ubuntu@ubuntu:~$ cd Downloads

ubuntu@ubuntu:~/Downloads$ unzip downgrade23.zip

Archive: downgrade23.zip

creating: desire_downgrade/

inflating: desire_downgrade/win-down.bat

inflating: desire_downgrade/rageagainstthecage-arm5.bin

inflating: desire_downgrade/downgrade.sh

inflating: desire_downgrade/cidlist.txt

inflating: desire_downgrade/fixmtd0.sh

inflating: desire_downgrade/mtd0.img

inflating: desire_downgrade/setup.sh

inflating: desire_downgrade/adb

inflating: desire_downgrade/checkfile.sh

inflating: desire_downgrade/cleanup.sh

inflating: desire_downgrade/flash_image

inflating: desire_downgrade/ChangeLog

inflating: desire_downgrade/AdbWinUsbApi.dll

extracting: desire_downgrade/PB99IMG.zip

inflating: desire_downgrade/adb.exe

extracting: desire_downgrade/mtd0.md5

inflating: desire_downgrade/AdbWinApi.dll

inflating: desire_downgrade/testroot.sh

extracting: desire_downgrade/PB99IMG.md5

inflating: desire_downgrade/fastboot.exe

inflating: desire_downgrade/busybox

inflating: desire_downgrade/get-cid.bat

inflating: desire_downgrade/adb-mac

inflating: desire_downgrade/root.sh

ubuntu@ubuntu:~/Downloads$ cd desire_downgrade

ubuntu@ubuntu:~/Downloads/desire_downgrade$ sudo ./downgrade.sh

Android 2.2 (froyo) to 2.1 downgrade utility.

=============================================

v2.2

For information, see this thread:

http://xdaforums.com/showthread.php?t=768256

Press ctrl-c to exit this utility.

Checking for device... Waiting for device. Ensure USB debugging is enabled.

* daemon not running. starting it now *

* daemon started successfully *

Pushing essential files.

567 KB/s (26172 bytes in 0.045s)

103 KB/s (5392 bytes in 0.050s)

1989 KB/s (655360 bytes in 0.321s)

6 KB/s (315 bytes in 0.045s)

5 KB/s (264 bytes in 0.048s)

6 KB/s (334 bytes in 0.047s)

17 KB/s (819 bytes in 0.044s)

2157 KB/s (1120536 bytes in 0.507s)

1 KB/s (55 bytes in 0.047s)

6 KB/s (304 bytes in 0.047s)

7 KB/s (364 bytes in 0.047s)

12 KB/s (625 bytes in 0.048s)

Done.

Pushing recovery image to the sdcard.

Press n and enter to skip this stage, or just press enter to continue:

Beginning transfer. This may take a minute or two...

1434 KB/s (144182346 bytes in 98.158s)

1 KB/s (54 bytes in 0.044s)

Now verifying the downgrade file.

Downgrade file passed verification.

Obtaining root access.

Please wait a moment.

Done.

* daemon not running. starting it now *

* daemon started successfully *

error: device not found

error: device not found

===================================================================

Your phone is now ready to be downgraded - rebooting to bootloader.

Starting in 10 seconds (ctrl-c to quit)

error: device not found

error: device not found

error: device not found

error: device not found

Complete.

* Now wait for the boot screen to appear.

* Press power to select the bootloader option.

* Wait for the recovery image to be located and checked.

* Press vol-up to start the update.

If you want to cancel the downgrade press vol-down.

Once flashed you can root your phone with unrevoked3.

Exiting.

ubuntu@ubuntu:~/Downloads/desire_downgrade$