How to cancel restore on Iphone 3G with broken Power Button?

I am really having a problem with my Power Button for a long time. I don't have enough money to replace my power button and I can't even use it anymore. And then I decided to restore my iPhone 3G because it was running too slow and I just have to get everything back to normal. But when I did, it says "error occured (1015)" which is a problem for jailbreaked iPhones. I just don't know what to do! I don't have a backup for my iPhone I just decided to create a new backup device. Please help me. I don't want to buy another phone.