SwapParity -> Unrecognized selector

[fivecord]

[__NSCFConstantString swapParity]: unrecognized selector sent to instance 0x120a28
It happens in the file NKDEAN13Barcode.m in the line
[theReturn appendString:[[self _encodeChar:contentString[i]] swapParity]];

I get the error with all EAN- and UPCA-barcode creation...

Does anyone have an idea how to solve it?

[netshade]

Can you try adding -ObjC to your "Other Linker Flags" in your project? That method is added via an NSString category in the project, and I believe that it's not being applied due to the lack of the -ObjC flag.