Hope i'm allowed to post this
Fix for WiFi 3GS after unlock with ultrasn0w Ver 0.8
Found this on site after trying everything I could find to get it to work for 3 days
Added a few more instruction
After unlock Iphone 3GS with ultrasn0w,your carrier working 100%!But wifi search failed!!
FIX YOUR WIFI!!!
Remove ultrasn0w in cydia!-->no carrier
Don't install ultrasn0w just jailbreak - follow instructions 2 onwards
Dowloads tool: ultrasn0w fixed!
Download iPhoneBrowser V188.8.131.52 ( Do Search Google )
Turn on wifi and connect to your Router - Network
Unzip the file you have just downloaded Ultrasn0w_Fixed
Connect Iphone to computer and run iPhoneBrowser ( Works like SSH )
In IphoneBroswer open folder Called Media
(source /private/var/root/Media )
In Media folder make a folder called Cydia
In the cydia folder make a folder called AutoInstall
Then copy the ultrasnow.debfile from zip file to AutoInstall forder!
Then go to the zip file: ultrasn0w/System/Libary/LaunchDaemons/ copy file: org.iphone-dev.ultrasn0w.plist to the same folder on the iphone with IphoneBrowser overwrite if necessary.
Then go back to zip file and go to: ultrasn0w/usr/bin/ copy file ultrasn0w to the same folder on the iphone as before.
Turn on the Airplane mode
Make sure you have the sim you want to use in the iphone
REBOOT you iphone Hold down both the power button and home button at same time until you see the apple logo then release
Go to WiFi first make sure it is working ( I have'nt turned mine back off since)
If all is well turn off Airplane mode and hopefully you should get carrier signal and WiFi
Think you will have to reboot after loading some apps or maybe turn off but have not tried.
If fix sync app failed
Copy intalled file to /usr/libexecand Sync app cracked!!