On Sun, Oct 9, 2011 at 18:01, Conal Elliott <conal@conal.net> wrote:
    /Library/Frameworks/Cairo.framework/Resources/dev/lib/libCairo.dylib: mach-o, but wrong architecture)

You have a set of native Gtk+ libraries from somewhere else.  They're not Apple's; you can try

    pkgutil --file-info /Library/Frameworks/Cairo.framework/Resources/dev/lib/libCairo.dylib

to see if there's an Installer receipt for it.  You'll probably need to remove all the related frameworks as well, and may then need to force rebuild the MacPorts libraries in case they managed to tangle themselves up in the unexpected framework(s).

brandon s allbery                                      allbery.b@gmail.com
wandering unix systems administrator (available)     (412) 475-9364 vm/sms