I've encountered the same problem as another user encountered on 64-bit linux with parsing of a 2D DWF image breaking out due to an Unsupported DWF Opcode. We are running 10.8.2, linking against our own build of the library (using Xcode 4.4.1) since the binary seemed to be 32-bit only and we are unable to switch to 32-bit builds.
I built the libraries from the DWFToolkit-7.7 source release. The modifications to the XCode project were somewhat minor although Xcode did want me to convert to llvm: aside from that, a few classes required use of this-> to access members; additionally, I disabled DWFCORE_BUILD_EXPAT as it wasn't happy with it and changed the target to OS X 10.8.
I'm hoping someone could help point out if I shoudl configure the project differently. I'm a bit new to XCode (used to Makefiles and such) so perhaps I missed something.
I'm attaching the file that is resulting in the errors. Let me know if there's any other info I should post. I'm going to work on a standalone program to confirm the same does not happen on 32-bit builds.