Call Failed issue after firmware downgrade

Recently i downgrade my firmware from 4.3.3 back to 4.1 simply because i get tired of the sluggish work of new firmware (shame on Apple).
Anyway, everything went smooth except one thing:
Every time i get a call and on the other line someone hang up i get this annoying Call Failure popup!!!!
It’s very disturbing because if i was in the middle of something with open app and get a call, normally after the call ends iPhone should automatically get back to the last app open but not anymore, now instead i get that annoying “call failed” screen.
After searching the web i understood that the issue happening because the baseband version witch 04.10.01 and it from 4.3.x firmware and i now on 4.1 firmware.
The only solution that i found (trust me i spend decent amount of time for searching) is download from Cydia popup Blocker and disable there Call failure popup, but unfortunately it doesn’t work in my case.

Please help me to resolve that issue before I switched to Android.

Thanks in advance.

 

What do you mean by saing "there is no other recourse" ?

 

I configured the iPhone as new so that's not the problem.