Haihui> when I try m-x jde-mode. it complains that run-mode-hooks Haihui> is void. When I open a cpp file, it says the Haihui> specification in run-mode-hooks is void , I don't know Haihui> what happened. GNU Emacs compatibility happened. That function isn't available in older GNU Emacs or any but the most recent XEmacs, but in recent GNU Emacs all packages use it. You need to upgrade XEmacs to 21.4.16 at least, preferably 21.4.17 as some known bugs in 21.4.16 were fixed. Cheers, -- School of Systems and Information Engineering http://turnbull.sk.tsukuba.ac.jp University of Tsukuba Tennodai 1-1-1 Tsukuba 305-8573 JAPAN Ask not how you can "do" free software business; ask what your business can "do for" free software.