iPhone 3G 3.0 stays stuck in sleep mode.

[triptych]

Hi

my issue begins when I make or receive a phone call with my pwned iphone, and it enters sleep mode after bringing it up to my ear. When I'm still on the call, hitting the home button doesn't wake it up with the screen remaining black. I can press the power button, but that hangs up with the caller...BUT, after pressing the Power button and then pressing the home button, the screen comes back to life. The other thing is that when it's stuck in sleep mode, and the person on the other end has hung up the phone, if they try to call again, I can hear it ringing but cannot answer it (unless I do the aforementioned power/home wakeup). Quite frustrating.

I've also tried rebooting it, but to no avail.

Any tips or solutions?

Cheers