Hi, I maintain an Elisp package that was developed for FSF EMacs but which I try and keep compatible with XEmacs. Recently an XEmacs user noted a compatability problem which I have tracked down to the simple.el package. In FSF Emacs they define a variable (undo-in-progress) that is set by the undo-more defun. This variable is primariliy available for before/after change functions to use to determine if a undo operation is in progress when they run. The differences are: FSF Emacs simple.el: (defvar undo-in-progress nil "Non-nil while performing an undo. Some change-hooks test this variable to do something different.") (defun undo-more (count) "Undo back N undo-boundaries beyond what was already undone recently. Call `undo-start' to get ready to undo recent changes, then call `undo-more' one or more times to undo them." (or pending-undo-list (error "No further undo information")) (let ((undo-in-progress t)) (setq pending-undo-list (primitive-undo count pending-undo-list)))) XEmacs simple.el: (defun undo-more (count) "Undo back N undo-boundaries beyond what was already undone recently. Call `undo-start' to get ready to undo recent changes, then call `undo-more' one or more times to undo them." (or pending-undo-list (error "No further undo information")) (setq pending-undo-list (primitive-undo count pending-undo-list) last-undo-buffer (current-buffer))) ; XEmacs Could you please add the defvar of undo-in-progress and the (let (undo-in-progress t) to the XEmacs file? Thanks Peter Peter Milliken Senior Software Engineer GTech Australasia Corp. Phone: +61 2 8233-6702 Fax: +61 2 8233-6784