iReb is an application designed to convert your device, that isn’t already jailbroken, into a temporary jailbroken state in the RAM to permit custom firmware created by Sn0wbreeze or PwnageTool. This tool is very helpful for most users that jailbreak there iDevice.
Download iREB 4.0 for iPhone 3G and iPod Touch 2G.
You could always get support from UnlockAlliPhone.com about any Unlock & JailBreak issue of any model of iPhone including iPhone 2G,3G & 3GS and also upcoming iPhone 4. They provide Premium Members Support for life time. Means just pay one time a small fee and you will receive support(real human support – avg response time 2 hour) for all present & future version of iPhone.