diff --git a/mailnews/base/resources/content/threadPane.xul b/mailnews/base/resources/content/threadPane.xul
index c364b8f26b8e..5044c9b53be8 100644
--- a/mailnews/base/resources/content/threadPane.xul
+++ b/mailnews/base/resources/content/threadPane.xul
@@ -83,19 +83,24 @@ Rights Reserved.
   </template>
 
   <treecolgroup id="theThreadColumns">
-	  <treecol persist="hidden width" fixed="true" width="20" id="ThreadColumn" rdf:resource="http://home.netscape.com/NC-rdf#Thread"/>
-	  <treecol persist="hidden width" width="7*" flex="7" id="SubjectColumn" rdf:resource="http://home.netscape.com/NC-rdf#Subject"/>
-    <treecol persist="hidden width" width="4*" flex="4" id="AuthorColumn" rdf:resource="http://home.netscape.com/NC-rdf#Sender"/>
-	  <treecol persist="hidden width" fixed="true" width="20" id="UnreadButtonColumn"/>
-	  <treecol persist="hidden width" width="2*" flex="2" id="DateColumn" rdf:resource="http://home.netscape.com/NC-rdf#Date"/>
-	  <treecol persist="hidden width" width="1*" flex="1" id="PriorityColumn" rdf:resource="http://home.netscape.com/NC-rdf#Priority"/>
-	  <treecol persist="hidden width" fixed="true" width="20" id="FlaggedButtonColumn"/>
-	  <treecol persist="hidden width" width="1*" flex="1" id="StatusColumn" rdf:resource="http://home.netscape.com/NC-rdf#Status"/>
-	  <treecol persist="hidden width" width="1*" flex="1" id="SizeColumn" rdf:resource="http://home.netscape.com/NC-rdf#Size"/>
-	  <treecol persist="hidden width" width="1*" flex="1" id="UnreadColumn" rdf:resource="http://home.netscape.com/NC-rdf#TotalUnreadMessages"/>
-	  <treecol persist="hidden width" width="1*" flex="1" id="TotalColumn" rdf:resource="http://home.netscape.com/NC-rdf#TotalMessages"/>
-	  <treecol persist="hidden width" fixed="true" width="1" id="OrderReceivedColumn" rdf:resource="http://home.netscape.com/NC-rdf#OrderReceived"/>
-	  <treecol persist="width" fixed="true" width="16" id="PopupColumn"/>
+	  <treecol persist="hidden width" id="ThreadColumn" rdf:resource="http://home.netscape.com/NC-rdf#Thread"/>
+    <treecol persist="hidden width" flex="7" id="SubjectColumn" rdf:resource="http://home.netscape.com/NC-rdf#Subject"/>
+    <splitter class="tree-splitter"/>
+    <treecol persist="hidden width" flex="4" id="AuthorColumn" rdf:resource="http://home.netscape.com/NC-rdf#Sender"/>
+	  <treecol persist="hidden width" id="UnreadButtonColumn"/>
+	  <treecol persist="hidden width" flex="2" id="DateColumn" rdf:resource="http://home.netscape.com/NC-rdf#Date"/>
+	  <splitter class="tree-splitter"/>
+    <treecol persist="hidden width" flex="1" id="PriorityColumn" rdf:resource="http://home.netscape.com/NC-rdf#Priority"/>
+    <treecol persist="hidden width" id="FlaggedButtonColumn"/>
+    <treecol persist="hidden width" flex="1" id="StatusColumn" rdf:resource="http://home.netscape.com/NC-rdf#Status"/>
+	  <splitter class="tree-splitter"/>
+    <treecol persist="hidden width" flex="1" id="SizeColumn" rdf:resource="http://home.netscape.com/NC-rdf#Size"/>
+	  <splitter class="tree-splitter"/>
+    <treecol persist="hidden width" flex="1" id="UnreadColumn" rdf:resource="http://home.netscape.com/NC-rdf#TotalUnreadMessages"/>
+	  <splitter class="tree-splitter"/>
+    <treecol persist="hidden width" flex="1" id="TotalColumn" rdf:resource="http://home.netscape.com/NC-rdf#TotalMessages"/>
+	  <treecol persist="hidden width" id="OrderReceivedColumn" rdf:resource="http://home.netscape.com/NC-rdf#OrderReceived"/>
+	  <treecol persist="width" id="PopupColumn"/>
   </treecolgroup>
 
   <treehead>
@@ -103,19 +108,19 @@ Rights Reserved.
 		<treecell display="Thread" onclick="return top.ChangeThreadView();" class="treecell-header treecell-inset-header threadColumnHeader" tooltip="aTooltip" tooltiptext="&threadColumnHeader.tooltip;" id="ThreadColumnHeader"/> 
 		<treecell class="treecell-header treecell-inset-header" value="&subjectColumn.label;" onclick="return top.MsgSortBySubject();"/>
 		<treecell class="treecell-header treecell-inset-header" onclick="return top.MsgSortBySender();" value="&senderColumn.label;" id="SenderColumnHeader"/>
-		<treecell class="treecell-header treecell-inset-header readColumnHeader" display="Read" onclick="return top.MsgSortByRead();"/> 
+		<treecell class="treecell-header treecell-header-image treecell-inset-header readColumnHeader" display="Read" onclick="return top.MsgSortByRead();"/> 
 		<treecell class="treecell-header treecell-inset-header" value="&dateColumn.label;" onclick="return top.MsgSortByDate();"/>
 		<treecell class="treecell-header treecell-inset-header" value="&priorityColumn.label;" onclick="return top.MsgSortByPriority();"/>
-		<treecell class="treecell-header treecell-inset-header flagColumnHeader" display="Flag" onclick="return top.MsgSortByFlagged();" />
+		<treecell class="treecell-header treecell-header-image treecell-inset-header flagColumnHeader" display="Flag" onclick="return top.MsgSortByFlagged();" />
 		<treecell class="treecell-header treecell-inset-header" value="&statusColumn.label;" onclick="return top.MsgSortByStatus();"/>
 		<treecell class="treecell-header treecell-inset-header" value="&sizeColumn.label;" onclick="return top.MsgSortBySize();"/>
 		<treecell class="treecell-header treecell-inset-header" value="&unreadColumn.label;" onclick="return top.MsgSortByUnread();"/>
 		<treecell class="treecell-header treecell-inset-header" value="&totalColumn.label;" onclick="return top.MsgSortByTotal();"/>
 		<treecell class="treecell-header treecell-inset-header" value="&orderReceivedColumn.label;" onclick="return top.MsgSortByOrderReceived();"/>
-		<treecell class="treecell-header treecell-inset-header" allowevents="true" id="popupCell" tooltip="aTooltip" tooltiptext="&columnChooser.tooltip;" autostretch="never">
+		<treecell class="treecell-header treecell-header-image treecell-inset-header" allowevents="true" id="popupCell" tooltip="aTooltip" tooltiptext="&columnChooser.tooltip;" autostretch="never">
 		  <menu>
-            <image src="chrome://global/skin/opentwisty.gif"/>
-			<menupopup popupanchor="bottomright" style="border: 1px solid green"
+            <image class="treecell-popup-icon"/>
+			<menupopup popupanchor="bottomright"
 			           popupalign="topright"
 					   oncreate="BuildTreePopup(document.getElementById('theThreadColumns'), document.getElementById('headRow'), this,
 			                                    document.getElementById('popupCell'))"/>