How to track gc problem?

Hi, I just got the terminal from where I started XEmacs, emacs-version "21.5 (beta26) \"endive\" (+CVS-20060507) XEmacs Lucid", filled with lines like this: ... ("(in garbage collection)" "[internal]") ("(in garbage collection)" "[internal]") ("(in garbage collection)" "[internal]") ... Before that there was some text suggesting me to stop XEmacs and I think there also was some gc stuff about a barrier!? When I eventually got to a terminal window and got some responce from it so that I could type a pkill there was nothing left but lots of those lines above. Is there something I can do to create some helpful info the next time this happens? Yours -- %% Mats