This is caused by the lack of the GTK1 pixmap engine. You can install it (and thus fix this issue) by apt-getting the __gtk- engines-pixmap__ package.
-- Gtk-WARNING **: Unable to locate loadable module in module_path: "libpixmap.so", https://launchpad.net/bugs/72469 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
