fix glitches caused by my 30536 checkin friday night

mailnews/base/prefs/resources/content/mailPrefsOverlay.xul

@@ -12,7 +12,8 @@
 
   <script language="JavaScript">
   <![CDATA[
-    if (panel) {
+    var panel;
+    if (panel != undefined) {
       switch(panel) 
       {
       case "chrome://communicator/content/pref/pref-advanced.xul":

xpfe/components/prefwindow/resources/content/pref.xul

@@ -84,7 +84,7 @@
 
   <box flex="1">
     <!-- tree sidebar -->
-    <tree class="inset" id="prefsTree" flex="1"/>      
+    <tree class="inset" id="prefsTree" flex="3"/>      
 
     <iframe id="panelFrame" name="panelFrame" style="width:0px" flex="7"/>
     <script language="JavaScript">