Just flash it via HBOOT.
1. Rename the file to PG88IMG.zip(not PG88IMG.zip.zip!)
2. Copy the file to the root of your SD card.
3. Restart you device into Recovery, and wipe cache and dalvik cache.(not necessarily needed, but recommended)
4. Restart your device into Bootloader
5. Press "power" button to acces HBOOT instead of fastboot
6. Wait 5-15sec, the bootloader is searching for uptades, if it findes the file, you can update the radio by pressing "vol up"
7. If it's finished, it says press "power" button to reboot, press it to finish.
Tested, working fine with old HBOOT, and also with new 2.00.0002 HBOOT.
GPS, WIFI, BT are all OK.
DOWNLOAD RADIO 20.48.30.0822U_3822.09.08.20_M(megaupload)
DOWNLOAD RADIO 20.48.30.0822U_3822.09.08.20_M MIRROR 1(hotfile)
DOWNLOAD RADIO 20.48.30.0822U_3822.09.08.20_M MIRROR 2(wupload)
radio.img MD5 80a39175defde876379e1c6b39bd1221
zip file MD5 18c0eeae21dfcd2145c4377ce69aa209
Update 1 [03 OCT 11]:
Added RIL from OTA. Download the rar file, unrar it, copy to your SD card, !make a backup!, copy and overwrite all 3 files in /system/lib (eg. with Rootexplorer, or ESExplorer), after that restart the phone, you're done.
If it was useful for you, don't forget to hit the thanks button.
Many thanks to cjward23!