Until xcode 4 final (I was using 3.latest and 4 GM for the time it was available) this didn\'t happen. When I upgraded to xcode 4 final version, I started getting a linking
Had the same problem.
But the reason was different I suppose.
I was using the library.a file built for simulator and trying to run it on device.. came to know that i need different .a files for simulator and device. I hope this helps someone ;)