Under Xcode 3.x and iOS 4, if an unhandled exception is signaled in the emulator there is an exception stack trace (similar to Java\'s) produced in the console output.
This is a known problem... for workarounds see here and here.
Another option might be to
defaults write NSGlobalDomain NSExceptionHandlingMask 63
Although it is usually for OSX it might help when using the emulator - I can't try it right now though :-(