21.0 assertion crash

This bug report will be sent to the XEmacs Development Team, not to your local site managers!! Please write in English, because the XEmacs maintainers do not have translators to read other languages for them. In XEmacs 21.0 "20 minutes to Nikko" [Lucid] (i686-pc-linux, Mule) of Thu Mar 25 1999 on myggen configured using `configure --with-mule' Please describe exactly what actions triggered the bug and the precise symptoms of the bug: I hadn't touched my XEmacs screen for a while, when suddenly it bombed on me. I was viewing a message in pgnus-0.79 when this happened: Fatal error: assertion failed, file insdel.c, line 364, VALID_CHARPTR_P (ptr) Fatal error (6) Lisp backtrace follows: extent-at(70 Fatal error: assertion failed, file insdel.c, line 364, VALID_CHARPTR_P (ptr) I was unable to locate the core file. Sorry. Recent keystrokes: M-x g n u s RET n n misc-user Recent messages (most recent first): flyspell on: #<buffer "*mail to xemacs-beta(a)xemacs.org*&quot;&gt; Loading mail-extr...done Loading mail-extr... Loading emacsbug...done Loading emacsbug... Checking new news...done Loading gnus-sum...done Loading gnus-sum... Opening nndraft server... Opening nntp server on news.fairplay.no... -- Erlend M. Simonsen / Fairplay International AS erlesimo(a)online.no / erlends(a)fairplay.no