I am totally stuck here and have spent 2 full days sifting through forums. Anyway I used blackra1n rc3 jailbreak for MAC with no problems on my new iPhone 3gs and installed a few apps, then had to reboot. After the reboot because it is tethered I had to make it ra1n again to make it reboot, again I had no problem, the geohot screen showed up and it rebooted fine.

I then installed winterboard which asked me to reboot again so I did thinking I would just need to make it ra1n again to reboot. However this time I have run into a problem that I cannot seem to fix, I hit make it ra1n as I did the previous times when it was stuck on the itunes usb screen and again the geohot screen showed up but this time after a few seconds instead of rebooting, the iPhone just shuts down. I hold power on and the apple logo comes up and it goes straight into recovery mode with the USB itunes screen, I have tried about 50 times now to make it ra1n and every time the same thing happens, the geohot screen shows up and the iPhone shuts down and when I try to start it goes into recovery mode.

Anyone have any ideas?