Unable to build i386 binary with XCode 4.0
keyring 0.6.2 setup.py has a section to empty ARCHFLAGS environment variable if it detects XCode 4.0. This is preventing building i386 binaries when you have XCode 4.0 installed, because you need to set ARCHFLAGS="-arch i386".
If you build with above flags and do lipo -info /path/to/keyring.so, it should show i386 binary. On Lion with XCode 4.0 I see x86_64.
I believe you should modify the setup code to remove all "-arch ppc\S*" instructions from ARCHFLAGS, not just clear it completely.