Now that Ted has added the #ifdefs (yeah, I hate those, too) to prefsdialog.* the build is working again. Thanks, Ted!
The Gtk::Socket docs say that it is implemented with X's XEMBED protocol, which of course will work on neither W32 nor native OSX. Kak zhal! Maybe Mozilla's source tree has a cross-platform way of mounting one process's gui in that of another. Gnome's Corba v.3 way (activation like ActiveX) of doing it is cross-platform, but of course that would lead to infinite dependencies.
I couldn't reply to the mail thread here, since this work email account is not receiving all of the messages that my home account does.
Anyway, the cvs build for this morning is: http://troi.hous.es3.titan.com/~rjamison/inkscape/builds/Inkscape0501130741....
Bob