Edit
#Edit HonestlyHonestly, I am not 100% sure that this was really a problem related to the kernel. I think that the "problem" could be also caused by the fact that pressing the home key in recovery mode results in a reboot. The correct way to select a recovery item is to press the power button.
Original post
#Original post II had the same issue two days ago. The problem was the kernel. After switching to the kernel that was mentioned a few wiki changes before it worked like a charm.
Kernel: http://cmw.22aaf3.com/aries/gt-i9000/root/Hardcore-speedmod-i9000.zip
MD5: afccda1f4efb560398dd5bc107bb7a69
I even (re-)added this information but it was again reverted. :-(