okay i got my iphone 3g and its jail broken from my friend and i wanted to erase everything on the phone so i went to settings and pushed erased all contents so after i took an hour to reboot it was finally done and then after that the apple logo just came on the screen and i have tryed everything from cutting it on and off and holding the home-button and power but its just stays on the apple logo. what should i do? please help thank you