iPhone is frozen

My iPhone froze like 1 hour ago. I just updated to 3.0 (jailbroken + unlocked) and then i changed my battery theme in winterboard. the springboard just got frozen when it was restarting. The iphone then closed and i turned it on. It just freezes at the apple logo and turns off after a while and back on. Please help
Answer #1
Hold Homebutton and Powerbutton together for something like 20seconds then you should be able to turn it back on
Answer #2
it turns back on by itself just doesnt get past the apple logo