I ran into a problem with a program that I work on where wxPython wasn't cutting it any longer, for various reasons (notably their current lack of support for 64-bit archs - see here). I wasn't really in love with wxPython, anyway, so I decided to ditch it in favor of Qt4, in combination with PyQt4 (which depends on sip for its C++ bindings).

While the general process of rewriting my GUI interface was pretty straightforward (given the decent tools in the Qt SDK + pyuic from PyQt4), I figured that packaging up the release was going to be painful. Call me crazy, but the shift to 64-bit in Snow Leopard should cause some issues with py2app working well for building bundles. It generally turns out that I was correct (don't get me wrong, I like py2app, it's just touchy).

I searched around for specific instructions on how to fix lots of the things that were broken. These included what I think was an endianness error, a typo in py2app's subversion code, mach-o build mismatches between sip-PyQt4-PyQt, and failure of py2app to add a directory to the bundle you build (i think that's it). Of most utility in my problem solving, I came across this thread which details many of the additions made (in the subversion trunk) to get py2app working, so thank you Marc-Antoine Parent. You are awesome. This post by Piotr Maliński was also helpful.

Long story short, for the moment, on Snow Leopard (10.6.2) with the system python, you need to do the following to make things work: