diff --git a/mailnews/base/resources/content/commandglue.js b/mailnews/base/resources/content/commandglue.js
index a54ac0210748..893c1c3237bf 100644
--- a/mailnews/base/resources/content/commandglue.js
+++ b/mailnews/base/resources/content/commandglue.js
@@ -120,7 +120,7 @@ function ComposeMessage(type, format)
 	var tree = GetThreadTree();
 	if (tree)
 	{
-		var nodeList = tree.getElementsByAttribute("selected", "true");
+		var nodeList = tree.selectedItems;
 		var appCore = FindMessenger();
 		if (appCore)
 			appCore.SetWindow(window, statusFeedback);
@@ -172,7 +172,7 @@ function NewMessage()
 function GetNewMessages()
 {
 	var folderTree = GetFolderTree();; 
-	var selectedFolderList = folderTree.getElementsByAttribute("selected", "true");
+	var selectedFolderList = folderTree.selectedItems;
 	if(selectedFolderList.length > 0)
 	{
 		var selectedFolder = selectedFolderList[0];
@@ -263,7 +263,7 @@ function MsgPreferences()
 function GetSelectedFolderResource()
 {
 	var folderTree = GetFolderTree();
-	var selectedFolderList = folderTree.getElementsByAttribute("selected", "true");
+	var selectedFolderList = folderTree.selectedItems;
 	var selectedFolder = selectedFolderList[0];
 	var uri = selectedFolder.getAttribute('id');
 
@@ -316,11 +316,13 @@ function ToggleMessageRead(treeItem)
 	messenger.MarkMessageRead(tree.database, treeItem, unread);
 }
 
-function ThreadPaneSelectionChange()
+function ThreadPaneSelectionChange(selectedElement)
 {
-	var doc = GetThreadPane().document;
+	var tree = GetThreadTree();
 	
-	var selArray = doc.getElementsByAttribute('selected', 'true');
+	var selArray = tree.selectedItems;
+	dump('In ThreadPaneSelectionChange().  Num Selected Items = ' + selArray.length);
+	dump('\n');
 	if ( selArray && (selArray.length == 1) )
 		LoadMessage(selArray[0]);
 	else
@@ -336,38 +338,32 @@ function ClearMessagePane()
 
 function GoNextMessage()
 {
-	var doc = GetThreadPane().document;
+	var tree = GetThreadTree();
 	
-	var selArray = doc.getElementsByAttribute('selected', 'true');
+	var selArray = tree.selectedItems;
 	if ( selArray && (selArray.length == 1) )
 	{
 		var nextMessage = GetNextMessage(selArray[0]);
 		if(nextMessage)
 		{
-			var selectedVal = selArray[0].getAttribute('selected');
-			dump('selectedVal = ' + selectedVal);
-
-			selArray[0].removeAttribute('selected');
-			nextMessage.setAttribute('selected', 'true');
+			tree.clearItemSelection();
+			tree.selectItem(nextMessage);
 		}
 	}
 }
 
 function GoNextUnreadMessage()
 {
-	var doc = GetThreadPane().document;
+	var tree = GetThreadTree();
 	
-	var selArray = doc.getElementsByAttribute('selected', 'true');
+	var selArray = tree.selectedItems;
 	if ( selArray && (selArray.length == 1) )
 	{
 		var nextMessage = GetNextUnreadMessage(selArray[0]);
 		if(nextMessage)
 		{
-			var selectedVal = selArray[0].getAttribute('selected');
-			dump('selectedVal = ' + selectedVal);
-
-			selArray[0].removeAttribute('selected');
-			nextMessage.setAttribute('selected', 'true');
+			tree.clearItemSelection();
+			tree.selectItem(nextMessage);
 		}
 	}
 }
diff --git a/mailnews/base/resources/content/threadPane.xul b/mailnews/base/resources/content/threadPane.xul
index e75bc5dc229b..fe291b9f565a 100644
--- a/mailnews/base/resources/content/threadPane.xul
+++ b/mailnews/base/resources/content/threadPane.xul
@@ -32,7 +32,7 @@ Rights Reserved.
 
 <html:div flex="100%">
 <tree style="height: 100%" datasources="rdf:null" id="threadTree"
-	  		  onchange="top.ThreadPaneSelectionChange()"
+	  		  onselect="top.ThreadPaneSelectionChange(event.target)"
 			  containment="http://home.netscape.com/NC-rdf#MessageChild">
 
   <template>
diff --git a/mailnews/base/resources/content/widgetglue.js b/mailnews/base/resources/content/widgetglue.js
index 7892ba297507..1b5cfd0a6946 100644
--- a/mailnews/base/resources/content/widgetglue.js
+++ b/mailnews/base/resources/content/widgetglue.js
@@ -76,7 +76,7 @@ function MsgDeleteMessage(fromToolbar)
 	}
 	dump("tree is valid\n");
 	//get the selected elements
-	var messageList = tree.getElementsByAttribute("selected", "true");
+	var messageList = tree.selectedItems;
 	//get the current folder
 	messenger.DeleteMessages(tree, srcFolder, messageList);
   }
@@ -86,7 +86,7 @@ function MsgDeleteFolder()
 {
 	//get the selected elements
 	var tree = GetFolderTree();
-	var folderList = tree.getElementsByAttribute("selected", "true");
+	var folderList = tree.selectedItems;
 	var i;
 	var folder, parent;
 	for(i = 0; i < folderList.length; i++)
@@ -148,9 +148,11 @@ function MsgCopyMessage(destFolder)
 	if(tree)
 	{
 		//Get the selected messages to copy
-		var messageList = tree.getElementsByAttribute("selected", "true");
+		var messageList = tree.selectedItems;
 		//get the current folder
 
+	//	dump('In copy messages.  Num Selected Items = ' + messageList.length);
+	//	dump('\n');
 		var srcFolder = GetThreadTreeFolder();
 		messenger.CopyMessages(tree.database, srcFolder, destFolder, messageList, false);
 	}	
@@ -166,7 +168,7 @@ function MsgMoveMessage(destFolder)
 	if(tree)
 	{
 		//Get the selected messages to copy
-		var messageList = tree.getElementsByAttribute("selected", "true");
+		var messageList = tree.selectedItems;
 		//get the current folder
 		var srcFolder = GetThreadTreeFolder();
 		messenger.CopyMessages(tree.database, srcFolder, destFolder, messageList, true);
@@ -236,7 +238,7 @@ function MsgSortBySubject()
 function MsgNewFolder()
 {
     var folderTree = GetFolderTree(); 
-	var selectedFolderList = folderTree.getElementsByAttribute("selected", "true");
+	var selectedFolderList = folderTree.selectedItems;
 	var selectedFolder = selectedFolderList[0];
     if (selectedFolder)
     {
@@ -252,7 +254,7 @@ function MsgNewFolder()
 function NewFolder(name)
 {
     var folderTree = GetFolderTree(); 
-	var selectedFolderList = folderTree.getElementsByAttribute("selected", "true");
+	var selectedFolderList = folderTree.selectedItems;
 	var selectedFolder = selectedFolderList[0];
 
 	messenger.NewFolder(folderTree.database, selectedFolder, name);
@@ -294,7 +296,7 @@ function MsgRenameFolder()
     var tree = GetFolderTree();
     if (tree)
     {
-        var folderList = tree.getElementsByAttribute("selected", "true");
+        var folderList = tree.selectedItems;
         if (folderList && folderList.length == 1)
         {
             var folder = folderList[0];
@@ -316,7 +318,7 @@ function RenameFolder(name)
     var tree = GetFolderTree();
     if (tree)
     {
-        var folderList = tree.getElementsByAttribute("selected", "true");
+        var folderList = tree.selectedItems;
         if (folderList && folderList.length == 1)
         {
             var folder = folderList[0];
@@ -331,7 +333,7 @@ function MsgEmptyTrash()
     var tree = GetFolderTree();
     if (tree)
     {
-        var folderList = tree.getElementsByAttribute("selected", "true");
+        var folderList = tree.selectedItems;
         if (folderList)
         {
             var folder;
@@ -354,7 +356,7 @@ function MsgCompactFolder()
 	var tree = GetFolderTree();
     if (tree)
     {
-        var folderList = tree.getElementsByAttribute("selected", "true");
+        var folderList = tree.selectedItems;
         if (folderList)
         {
             var i;
@@ -469,7 +471,7 @@ function MsgMarkMsgAsRead(markRead)
   dump("\MsgMarkMsgAsRead from XUL\n");
   var tree = GetThreadTree();
   //get the selected elements
-  var messageList = tree.getElementsByAttribute("selected", "true");
+  var messageList = tree.selectedItems;
   messenger.MarkMessagesRead(tree.database, messageList, markRead);
 }
 
@@ -478,7 +480,7 @@ function MsgMarkByDate() {}
 function MsgMarkAllRead()
 {
 	var folderTree = GetFolderTree();; 
-	var selectedFolderList = folderTree.getElementsByAttribute("selected", "true");
+	var selectedFolderList = folderTree.selectedItems;
 	if(selectedFolderList.length > 0)
 	{
 		var selectedFolder = selectedFolderList[0];
diff --git a/mailnews/base/resources/locale/en-US/messenger.dtd b/mailnews/base/resources/locale/en-US/messenger.dtd
index 32cd8659ab23..1357013928ff 100644
--- a/mailnews/base/resources/locale/en-US/messenger.dtd
+++ b/mailnews/base/resources/locale/en-US/messenger.dtd
@@ -183,9 +183,9 @@ Rights Reserved.
 <!ENTITY goMenu.label ".Go"> 
 <!ENTITY firstUnreadMsgCmd.label ".First Unread Message">  
 <!ENTITY firstFlaggedMsgCmd.label ".First Flagged Message">  
-<!ENTITY nextMenu.label ".Next"> 
-<!ENTITY nextMsgCmd.label ".Message">  
-<!ENTITY nextUnreadMsgCmd.label ".Unread Message">  
+<!ENTITY nextMenu.label "Next"> 
+<!ENTITY nextMsgCmd.label "Message">  
+<!ENTITY nextUnreadMsgCmd.label "Unread Message">  
 <!ENTITY nextFlaggedMsgCmd.label ".Flagged Message">  
 <!ENTITY prevMenu.label ".Previous"> 
 <!ENTITY prevMsgCmd.label ".Message">  
diff --git a/mailnews/base/resources/locale/en-US/threadpane.dtd b/mailnews/base/resources/locale/en-US/threadpane.dtd
index 07e5940f7fb0..84f589bb2581 100644
--- a/mailnews/base/resources/locale/en-US/threadpane.dtd
+++ b/mailnews/base/resources/locale/en-US/threadpane.dtd
@@ -18,6 +18,7 @@ Communications Corporation. Portions created by Netscape are
 Rights Reserved.
 --> 
 
+<!ENTITY threadColumn.label "Thread">
 <!ENTITY senderColumn.label "Sender">
 <!ENTITY subjectColumn.label "Subject">
 <!ENTITY dateColumn.label "Date">
diff --git a/suite/locales/en-US/chrome/mailnews/messenger.dtd b/suite/locales/en-US/chrome/mailnews/messenger.dtd
index 32cd8659ab23..1357013928ff 100644
--- a/suite/locales/en-US/chrome/mailnews/messenger.dtd
+++ b/suite/locales/en-US/chrome/mailnews/messenger.dtd
@@ -183,9 +183,9 @@ Rights Reserved.
 <!ENTITY goMenu.label ".Go"> 
 <!ENTITY firstUnreadMsgCmd.label ".First Unread Message">  
 <!ENTITY firstFlaggedMsgCmd.label ".First Flagged Message">  
-<!ENTITY nextMenu.label ".Next"> 
-<!ENTITY nextMsgCmd.label ".Message">  
-<!ENTITY nextUnreadMsgCmd.label ".Unread Message">  
+<!ENTITY nextMenu.label "Next"> 
+<!ENTITY nextMsgCmd.label "Message">  
+<!ENTITY nextUnreadMsgCmd.label "Unread Message">  
 <!ENTITY nextFlaggedMsgCmd.label ".Flagged Message">  
 <!ENTITY prevMenu.label ".Previous"> 
 <!ENTITY prevMsgCmd.label ".Message">  
diff --git a/suite/locales/en-US/chrome/mailnews/threadpane.dtd b/suite/locales/en-US/chrome/mailnews/threadpane.dtd
index 07e5940f7fb0..84f589bb2581 100644
--- a/suite/locales/en-US/chrome/mailnews/threadpane.dtd
+++ b/suite/locales/en-US/chrome/mailnews/threadpane.dtd
@@ -18,6 +18,7 @@ Communications Corporation. Portions created by Netscape are
 Rights Reserved.
 --> 
 
+<!ENTITY threadColumn.label "Thread">
 <!ENTITY senderColumn.label "Sender">
 <!ENTITY subjectColumn.label "Subject">
 <!ENTITY dateColumn.label "Date">