I think this bug is more suited to upstream attention. Evolution still uses a GNOME about dialog instead of a GtkAboutDialog.
There is a proposal to change all GNOME applications to a new layout of about dialogue - http://live.gnome.org/GnomeGoals/AboutDialog -- Evolution should use GtkAboutDialog https://launchpad.net/bugs/3226 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs