htc desire z root shell I'm trying only to get a root shell, not persistent, don't want to flash any kind of image or install closed/proprietary apk, nor run scripts/exploits that write/erase/modify any flash.

For a newer device has been just a matter of few mins, found an exploit, compiled, pushed, executed, got the root shell, instead this one seem to be unbreakable, already spent hours trying different approaches :-|

2.6.35.10-g53a84f9 (htc-kernel@and18-2) - Android/2.3.3

Suggestions?
zergRush did it, seems to be the only one working, I just did some personal change to not remount /data and not set any property but just chmod an adb pre-pushed /data/local/tmp/su.