In XEmacs 21.1 (patch 4) "Arches" [Lucid] (i386-pc-win32) of Tue Jul 27 1999 on GLENN configured using `configure UNKNOWN' Please describe exactly what actions triggered the bug and the precise symptoms of the bug: Start xemacs with "xemacs -vanilla <somefile>" where <somefile> is a file with more lines than fit into the frame, so that it is possible to scroll up and down. Scroll up and down using the wheel on Microsoft Intellimouse. Everything works as expected. Type M-x:lazy-lock-mode and then try to scroll as before. XEmacs instantly hangs for anything ranging from 5 to 60 seconds. -- Glenn Coombs (gc(a)aslnet.co.uk) Application Solutions Ltd. Tel: +44 (0) 1273 476608 Fax: +44 (0) 1273 478888