Why is my ipod touch going to a black screen and not jail breaking?

I am using windows xp to jail break my ipod touch 2 gen with 3.1.2 firmware. Blackra1n says my ipod is jail broken, but when my ipod reboots it is normal and unjail broken. I have tried it about 50 times to use blackra1n but nothing seems to work. If anyone has had this same problem and found a solution would you please help me. Best answer to anyone who solves this problem.Thanks.

http://www.youtube.com/watch?v=7EocyXqXBIM try this vid, first watch it then click on the 3.1.2 link to get the files and stuff, its called pwnage.