64-bit PyQt4 on Mac?

Hi, I'm trying to install PyQt4 so I can use Qt as a matplotlib backend.

I can't figure out how to get PyQt4 to compile 64 bit.

$ file /Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/PyQt4/QtCore.so
/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/PyQt4/QtCore.so: Mach-O bundle i386

I've tried setting CFLAGS="-arch ppc7400 -arch ppc64 -arch i386 -arch x86_64", but that doesn't add the x86_64 architecture to QtCore.so.

Any idea how I can get 64-bit PyQt running?

Thanks,
Adam