Comment 4 for bug 400165

This problem actually started happening for me in the last couple of days after upgrading Macports.

It is fixed in svn in r21860. I will build an upload a new 0.47 package in the morning.

The problem is Inkscape trying to read incompatible fontcaches from Macports. The fix is to modify Inkscape.app/Contents/Resources/etc/fonts/fonts/conf to remove the following line:
 <cachedir>/opt/local/var/cache/fontconfig</cachedir>

(Also, FWIW DYLD_LIBRARY_PATH does override the install-names. This wasn't an issue. But, I recently had a go at rewriting the install-names to thus not require DYLD_LIBRARY_PATH anymore. But the problem is that the path we require it too long for the space allocated to the install names in some libraries, so we might need to try doing something sneaky like installing macports in a prefix with a long name.)