[N.B. I posted this on comp.emacs.xemacs a week ago. A cc of any discussion would be appreciated. Thanks.] Xemacs 21.4.4 If font-lock-syntactic-keywords (that's the thing with which font-lock applies individual syntax codes to some characters in a buffer, with the intention of later fontifying these accordingly) is set, then... ... it (font-lock-syntactic-keywords) passes into the function font-lock-compile-keywords, where its value is overwrites font-lock-keywords, because of an unfortunate setq. This visible effect of this is to disable keyword fontification. The following patch fixes it (at least, it does for me :-). I had a quick peep at the latest (about a week ago) CVS version. The bug hadn't been fixed there yet, either. Incidentally, <http://www.xemacs.org/lists/index.html> doesn't seem to state explicitly what the addresses of the mailing lists are. I have assumed that xemacs-beta(a)xemacs.org is correct (I'm not expecting a bounce), but I think an explicit address would be helpful. 2002-09-20 Alan Mackenzie <acm(a)muc.de&gt; * font-lock.el: Remove spurious setq from font-lock-compile-keywords. *** font-lock-21.4.4.el Fri Sep 20 18:00:32 2002 --- font-lock.el Fri Sep 20 19:53:08 2002 *************** *** 1597,1603 **** (let* ((case-fold-search font-lock-keywords-case-fold-search) (keywords (cdr (if (eq (car-safe font-lock-keywords) t) font-lock-keywords ! (font-lock-compile-keywords)))) (bufname (buffer-name)) (progress 5) (old-progress 5) (iter 0) --- 1597,1604 ---- (let* ((case-fold-search font-lock-keywords-case-fold-search) (keywords (cdr (if (eq (car-safe font-lock-keywords) t) font-lock-keywords ! (setq font-lock-keywords ! (font-lock-compile-keywords font-lock-keywords))))) (bufname (buffer-name)) (progress 5) (old-progress 5) (iter 0) *************** *** 1671,1684 ****  ;; Various functions. ! (defun font-lock-compile-keywords (&optional keywords) ! ;; Compile `font-lock-keywords' into the form (t KEYWORD ...) where KEYWORD ! ;; is the (MATCHER HIGHLIGHT ...) shown in the variable's doc string. ! (let ((keywords (or keywords font-lock-keywords))) ! (setq font-lock-keywords ! (if (eq (car-safe keywords) t) ! keywords ! (cons t (mapcar 'font-lock-compile-keyword keywords)))))) (defun font-lock-compile-keyword (keyword) (cond ((nlistp keyword) ; Just MATCHER --- 1672,1685 ----  ;; Various functions. ! (defun font-lock-compile-keywords (keywords) ! ;; Compile `font-lock-\(syntactic-\)?keywords' into the form (t KEYWORD ...) ! ;; where KEYWORD is the (MATCHER HIGHLIGHT ...) shown in the variable's doc ! ;; string. ! ;; (setq font-lock-keywords NO! NO! KEYWORDS is sometimes f-l-syntactic-k ! (if (eq (car-safe keywords) t) ! keywords ! (cons t (mapcar 'font-lock-compile-keyword keywords)))) (defun font-lock-compile-keyword (keyword) (cond ((nlistp keyword) ; Just MATCHER -- Alan Mackenzie (Munich, Germany) acm(a)muc.de