I'm getting this error when building my iPhone application:
ld: warning: in /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.sdk/System/Library
/Frameworks/UIKit.framework/UIKit, missing required architecture i386 in file
It goes the same for all the frameworks in my app. It's very weird since this was not happening earlier.
Best Answer
This happens when you add a framework to your project and unintentionally copy the framework into your project directory.
The fix is to check your project directory (where you store your project on disk) for any iphone SDK *.Framework files and delete them.
Project will build fine afterwards.