This is took from untermensch's thread in the Vibrant forum so I take no credit for this (http://forum.xda-developers.com/showthread.php?t=833423)
I have noticed some of you are having issues after installing a new kernel or rom, when you boot into recovery you now have 3e, which does not allow unsigned zips to be flashed. With this version of 3e it has no-verification check, now allowing you to flash whatever you want.
This zip has
1) 3e recovery modified to disable signature checking
2) disables the forced wipe after installing any update.
1)Download and extract the file below
2)Use a terminal emulator or ADB shell and type.. (or you can use Root Explorer or SGSTools to mount system RW)
mount -o rw,remount /dev/block/stl9 /system
4)Now, reboot and you should have a modded 3e recovery with no signature verification
You can either leave the modded 3e recovery or you can now flash CWM via Rom Manager
**Just like anything else, I am not responsible if this bricks your phone, this is fairly simple, follow the guide...Do at your own risk**