After upgrading to iOS 5 the actual phone app keeps crashing

Updated my iPhone 4 to iOS 5 yesterday. Everything seems to work fine, it seems, except the actual phone app.

When I click it to make a call it immediately crashes and goes back to the home screen.

I was able to make a call by calling out of the address book but the screen was blank. At the top I got the green bar saying "Touch to return to call" and when I clicked on it I'd see the regular phone stuff you'd expect to see for a split second before the screen went back to black with the green bar at the top.

I was unable to end the call without turning the phone off.

I can receive calls and everything works fine until I answer the call. I'm able to talk with no problems but I get the same problem described above when actually looking at the phone.

I have tried turning the phone off and also hard resets but nothing works.

Anybody know what's wrong or how to fix?

Thanks,

d.

After clearing all apps out of the multitask tray it still didn't work but I then did a hard reset and it appears to work fine now.

Thanks for the suggestion. I never would have thought of that on my own.

It appears I spoke too soon.

Just received a call and after it was done went to hang up and noticed the "return to call" green bar at the top.

The caller hung up before I could touch it but just went back into phone app and it crashed again just like before.

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Also this thing is eating battery power like it's going out of style. Ever since this morning when I went into a building where I lose the 3G network and it goes to Edge. To get back to 3G after leaving this building I always have to turn the phone off and on.

Lost 3 percentage points since I started typing my previous reply.

what fixed it for me was wiping the phone and reinstalling it again. i can't remember if i started from scratch or from a back up.