What about the ediff control buffer? If you set ediff-window-setup-function
to ediff-setup-windows-multiframe, i.e. use a separate frame for the ediff
control panel, and have gutter visible, XEmacs crashes when the mouse
pointer enters the ediff control buffer (I reported this some time ago:
http://www.xemacs.org/list-archives/xemacs-beta/199911/msg00101.html).
Does this fix also cover this issue? Or is it a completely different story?
Markus