fahd, no results in google? it's called a reboot loop, or that is the phrase most people use to describe this problem. Lots of hits on google using "reboot loop maemo". (Admitted: Finding stuff with google very much depends on how well you are able to describe what you want.)

Difficult, you ask? No, it's not hard at all. It's mainly a matter of being precise when you're doing it, so follow the wiki/tutorials around to the letter. And of course, the first time it's a bit scary perhaps, but the second time already less, etc.

For the rest: What m4r0v3r said.