Index: xul/content/output-base.css
===================================================================
RCS file: /cvsroot/mozilla/extensions/irc/xul/content/output-base.css,v
retrieving revision 1.17
retrieving revision 1.18
diff -d -p -u -6 -r1.17 -r1.18
--- xul/content/output-base.css	8 Mar 2008 09:44:37 -0000	1.17
+++ xul/content/output-base.css	8 Mar 2008 13:23:08 -0000	1.18
@@ -499,12 +499,14 @@ a.chatzilla-link:hover {
     white-space: nowrap;
 }
 
 .msg-data {                                 /* .msg-data = the text portion   */
     padding: 1px 1px 1px 3px;               /* of a message                   */
     width: 100%;
+    /* need to set this twice for back+forward compat, see bug 418543 */
+    white-space: -moz-pre-wrap;
     white-space: pre-wrap;
 }
 
 
 /******************************************************************************
  * message class specific definitions                                         *