diff --git a/calendar/resources/content/calendar.js b/calendar/resources/content/calendar.js
index 0737710e0451..5abd91cc6a3c 100644
--- a/calendar/resources/content/calendar.js
+++ b/calendar/resources/content/calendar.js
@@ -249,6 +249,9 @@ function calendarInit()
 
    //All is settled, enable feedbacks to observers
    gICalLib.batchMode = false;
+
+   var toolbox = document.getElementById("calendar-toolbox");
+   toolbox.customizeDone = CalendarToolboxCustomizeDone;
 }
 
 // Set the date and time on the clock and set up a timeout to refresh the clock when the 
@@ -1599,3 +1602,30 @@ function srGetStrBundle(path)
   }
   return strBundle;
 }
+
+function CalendarCustomizeToolbar()
+{
+  // Disable the toolbar context menu items
+  var menubar = document.getElementById("main-menubar");
+  for (var i = 0; i < menubar.childNodes.length; ++i)
+    menubar.childNodes[i].setAttribute("disabled", true);
+    
+  var cmd = document.getElementById("cmd_CustomizeToolbars");
+  cmd.setAttribute("disabled", "true");
+  
+  window.openDialog("chrome://calendar/content/customizeToolbar.xul", "CustomizeToolbar",
+                    "chrome,all,dependent", document.getElementById("calendar-toolbox"));
+}
+
+function CalendarToolboxCustomizeDone(aToolboxChanged)
+{
+  // Re-enable parts of the UI we disabled during the dialog
+  var menubar = document.getElementById("main-menubar");
+  for (var i = 0; i < menubar.childNodes.length; ++i)
+    menubar.childNodes[i].setAttribute("disabled", false);
+  var cmd = document.getElementById("cmd_CustomizeToolbars");
+  cmd.removeAttribute("disabled");
+
+  // XXX Shouldn't have to do this, but I do
+  window.focus();
+}
diff --git a/calendar/resources/locale/en-US/calendar.dtd b/calendar/resources/locale/en-US/calendar.dtd
index 8e4bd0779a24..933383fbb524 100644
--- a/calendar/resources/locale/en-US/calendar.dtd
+++ b/calendar/resources/locale/en-US/calendar.dtd
@@ -294,6 +294,12 @@
 <!-- Window Title -->
 <!ENTITY window.title            "Mozilla Calendar">
 
+<!-- customizable toolbars -->
+<!ENTITY calendar.context.customize.label             "Customize">
+<!ENTITY calendar.context.customize.accesskey         "C">
+<!ENTITY calendar.maintoolbar.name                    "Main Toolbar">
+<!ENTITY calendar.maintoolbar.accesskey               "M">
+
 <!-- Context Menu -->
 <!ENTITY calendar.context.newevent.label              "New Event">
 <!ENTITY calendar.context.newevent.accesskey          "N">
diff --git a/calendar/resources/skin/classic/calendar.css b/calendar/resources/skin/classic/calendar.css
index 2db4a6718123..bf06ffc52306 100644
--- a/calendar/resources/skin/classic/calendar.css
+++ b/calendar/resources/skin/classic/calendar.css
@@ -64,6 +64,7 @@
 
 .toolbarbutton-1 {
   list-style-image: url("chrome://calendar/skin/btn1.png");
+  -moz-box-orient: vertical;
 }
 
 
diff --git a/calendar/sunbird/app/profile/sunbird.js b/calendar/sunbird/app/profile/sunbird.js
index df113664fe55..84a2f64f1e59 100644
--- a/calendar/sunbird/app/profile/sunbird.js
+++ b/calendar/sunbird/app/profile/sunbird.js
@@ -41,7 +41,7 @@
 // pref("startup.homepage_override_url","chrome://browser-region/locale/region.properties");
 pref("general.startup.calendar", true);
 
-pref("browser.chromeURL","chrome://browser/content/");
+pref("browser.chromeURL","chrome://calendar/content/");
 pref("browser.hiddenWindowChromeURL", "chrome://browser/content/hiddenWindow.xul");
 pref("xpinstall.dialog.confirm", "chrome://mozapps/content/xpinstall/xpinstallConfirm.xul");
 pref("xpinstall.dialog.progress", "chrome://mozapps/content/downloads/downloads.xul");
diff --git a/calendar/sunbird/base/content/calendar.xul b/calendar/sunbird/base/content/calendar.xul
index cdec9b5d1374..8dd19c0a825c 100644
--- a/calendar/sunbird/base/content/calendar.xul
+++ b/calendar/sunbird/base/content/calendar.xul
@@ -47,7 +47,6 @@
 <?xml-stylesheet href="chrome://global/skin/global.css" type="text/css"?> 
 <?xml-stylesheet href="chrome://calendar/skin/calendar.css" type="text/css"?>
 <?xml-stylesheet href="chrome://calendar/content/datetimepickers/minimonth.css" type="text/css"?>
-<?xml-stylesheet href="chrome://communicator/skin/communicator.css" type="text/css"?>
 
 <!-- Overlays -->
 <?xul-overlay href="chrome://global/content/globalOverlay.xul"?>
@@ -132,6 +131,8 @@
    <command id="close_calendar_command" key="key_close" oncommand="closeCalendar()"/>
    
    <command id="wizard_command" oncommand="launchWizard()" collapsed="true"/>
+
+   <command id="cmd_CustomizeToolbars" oncommand="CalendarCustomizeToolbar()"/>
 </commandset>
 
 <keyset>
@@ -403,14 +404,23 @@
              observes="publish_calendar"/>
 </popup>
 
+<popup id="toolbar-context-menu">
+  <menuitem command="cmd_CustomizeToolbars"
+            label="&calendar.context.customize.label;"
+            accesskey="&calendar.context.customize.accesskey;"/>
+</popup>
+
 <commandset id="commands"/>
 
-<toolbox id="calendar-toolbox" class="toolbox-top" deferattached="true">
+<toolbox id="calendar-toolbox" class="toolbox-top">
    <!-- Menu -->
-   <menubar id="main-menubar" persist="collapsed"/>
+   <toolbar type="menubar" id="main-menubar" class="chromeclass-menubar" customizable="true"
+            defaultset="menubar-items"
+            mode="icons" iconsize="small" context="toolbar-context-menu">
+      <toolbaritem id="menubar-items" align="center"/>
+   </toolbar>
 
-   <toolbar class="toolbar-primary chromeclass-toolbar" id="calendar-bar" persist="collapsed" tbalign="stretch">
-		<!--<toolbarbutton class="toolbarbutton-1" id="calendar-new-task-button"   label="&calendar.newtask.button.label;"         tooltiptext="&calendar.newtask.button.tooltip;"      observes="new_todo_command"/>-->
+   <toolbarpalette id="calendarToolbarPalette">
       <toolbarbutton class="toolbarbutton-1"
                      id="calendar-new-event-button"
                      label="&calendar.newevent.button.label;"
@@ -426,7 +436,6 @@
                      label="&calendar.delete.button.label;"
                      tooltiptext="&calendar.delete.button.tooltip;"
                      observes="delete_command"/>
-      <toolbarseparator class="toolbarseparator-primary"/>
       <toolbarbutton class="toolbarbutton-1"
                      id="calendar-day-view-button"
                      label="&calendar.dayview.button.label;"
@@ -448,14 +457,19 @@
                      tooltiptext="&calendar.monthview.button.tooltip;"
                      observes="month_view_command"/>
 
-      <spacer flex="1"/>
-
       <toolbaritem id="throbber-box" align="center" pack="center">
          <button id="navigator-throbber2" 
                  oncommand="openAboutDialog();"
                  tooltiptext="&aboutCmd.label;"/>
       </toolbaritem>
-   </toolbar>
+   </toolbarpalette>
+   <toolbar class="toolbar-primary chromeclass-toolbar" id="calendar-bar"
+            iconsize="big"
+            defaultset="calendar-new-event-button,calendar-edit-event-button,calendar-delete-event-button,separator,calendar-day-view-button,calendar-week-view-button,calendar-multiweek-view-button,calendar-month-view-button,spring,throbber-box"
+            customizable="true" mode="full"
+            toolbarname="&calendar.maintoolbar.name;" accesskey="&calendar.maintoolbar.accesskey;"
+            context="toolbar-context-menu"/>
+   <toolbarset id="customToolbars" context="toolbar-context-menu"/>
 </toolbox>
 
 <tooltip id="eventTreeListTooltip" onpopupshowing="changeToolTipTextForEvent( event );return( checkTooltip( event ) );"/>
@@ -527,10 +541,7 @@
             </tabpanel>
             </tabpanels>
          </tabbox>
-         <splitter id="calendar-todo-splitter" collapse="before" persist="state"
-            class="chromeclass-extrachrome" orient="vertical">
-            <grippy/>
-         </splitter>
+         <splitter id="calendar-todo-splitter" collapse="before" persist="state" orient="vertical"/>
          <vbox id="left-hand-below-splitter" flex="1" persist="height">
             <box align="left">
                <label flex="1" crop="end" style="font-weight: bold" value="&calendar.unifinder.todoitems.label;"/>
@@ -595,9 +606,8 @@
          </vbox>
     
          <splitter id="calendar-splitter" collapse="before" persist="state"
-          class="chromeclass-extrachrome sidebar-splitter" orient="horizontal" onmouseup="setTimeout( 'gCalendarWindow.onMouseUpCalendarSplitter()', 1 );">
-            <grippy class="sidebar-splitter-grippy"/>
-         </splitter>
+                   class="chromeclass-extrachrome sidebar-splitter" orient="horizontal"
+                   onmouseup="setTimeout( 'gCalendarWindow.onMouseUpCalendarSplitter()', 1 );"/>
          
          <vbox flex="1">
             <vbox id="bottom-events-box" persist="height">
diff --git a/calendar/sunbird/base/content/customizeToolbar.xul b/calendar/sunbird/base/content/customizeToolbar.xul
new file mode 100644
index 000000000000..3af8fcd7355b
--- /dev/null
+++ b/calendar/sunbird/base/content/customizeToolbar.xul
@@ -0,0 +1,93 @@
+<?xml version="1.0"?> 
+
+# The contents of this file are subject to the Netscape Public
+# License Version 1.1 (the "License"); you may not use this file
+# except in compliance with the License. You may obtain a copy of
+# the License at http://www.mozilla.org/NPL/
+# 
+# Software distributed under the License is distributed on an "AS
+# IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+# implied. See the License for the specific language governing
+# rights and limitations under the License.
+# 
+# The Original Code is Mozilla Communicator client code, released
+# March 31, 1998.
+# 
+# The Initial Developer of the Original Code is Netscape
+# Communications Corporation. Portions created by Netscape are
+# Copyright (C) 1998-1999 Netscape Communications Corporation. All
+# Rights Reserved.
+# 
+# Contributor(s): 
+#   David Hyatt (hyatt@apple.com)
+#   Blake Ross (blaker@netscape.com)
+
+<!DOCTYPE dialog [
+<!ENTITY % customizeToolbarDTD SYSTEM "chrome://global/locale/customizeToolbar.dtd">
+  %customizeToolbarDTD;
+]>
+
+<?xml-stylesheet href="chrome://global/skin/" type="text/css"?>
+<?xml-stylesheet href="chrome://global/content/customizeToolbar.css" type="text/css"?>
+<?xml-stylesheet href="chrome://global/skin/customizeToolbar.css" type="text/css"?>
+
+<window id="CustomizeToolbarWindow"
+        title="&dialog.title;"
+        onload="onLoad();"
+        onunload="onUnload();"
+        onclose="onAccept(); return false;"
+        xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+<script type="application/x-javascript">
+  <![CDATA[
+    toolbox = window.arguments[0];
+    toolboxDocument = toolbox.ownerDocument;
+
+    var sheetList = toolboxDocument.styleSheets;
+    for (var i=0; i < sheetList.length; ++i) {
+      var newPI = document.createProcessingInstruction("xml-stylesheet", 'href="'+sheetList[i].href+'" type="text/css"');
+      document.insertBefore(newPI, document.firstChild);    
+    }
+  ]]>
+</script>
+
+<script type="application/x-javascript" src="chrome://global/content/customizeToolbar.js"/>
+<script type="application/x-javascript" src="chrome://global/content/nsDragAndDrop.js"/>
+<script type="application/x-javascript" src="chrome://global/content/nsTransferable.js"/>
+
+<stringbundle id="stringBundle" src="chrome://global/locale/customizeToolbar.properties"/>
+
+<vbox id="main-box" flex="1" collapsed="true">
+  <description id="instructions">
+  &instructions.description;
+  </description>
+
+  <vbox flex="1" id="palette-box"
+        ondraggesture="gDraggingFromPalette = true; nsDragAndDrop.startDrag(event, dragStartObserver);"
+        ondragover="nsDragAndDrop.dragOver(event, paletteDNDObserver);"
+        ondragdrop="nsDragAndDrop.drop(event, paletteDNDObserver);"/>
+
+  <box align="center">
+    <label value="&show.label;"/>
+    <menulist id="modelist" value="icons" oncommand="updateToolbarMode(this.value);">
+      <menupopup>
+        <menuitem value="full" label="&iconsAndText.label;"/>
+        <menuitem value="icons" label="&icons.label;"/>
+        <menuitem value="text" label="&text.label;"/>
+      </menupopup>
+    </menulist>
+    
+    <checkbox id="smallicons" oncommand="updateIconSize(this.checked);" label="&useSmallIcons.label;"/>
+    
+    <button label="&addNewToolbar.label;" oncommand="addNewToolbar();"/>
+    <button label="&restoreDefaultSet.label;" oncommand="restoreDefaultSet();"/>
+  </box>
+
+  <separator class="groove"/>
+
+  <hbox align="center" pack="end">
+    <button label="&saveChanges.label;" oncommand="onAccept();" default="true"/>
+  </hbox>
+</vbox>
+
+</window>
diff --git a/calendar/sunbird/base/content/menuOverlay.xul b/calendar/sunbird/base/content/menuOverlay.xul
index 98925b87f0d7..5fae351f6a37 100644
--- a/calendar/sunbird/base/content/menuOverlay.xul
+++ b/calendar/sunbird/base/content/menuOverlay.xul
@@ -89,11 +89,12 @@
 
   
   <!-- Menu -->
-  <menubar id="main-menubar" class="chromeclass-menubar">
-   <menu id="menu_File"
-    label="&fileMenu.label;"
-     accesskey="&fileMenu.accesskey;">
-      <menupopup id="menu_FilePopup">
+  <toolbaritem id="menubar-items">
+    <menubar id="main-menubar" style="border:0px;padding:0px;margin:0px;-moz-appearance:none">
+     <menu id="menu_File"
+           label="&fileMenu.label;"
+           accesskey="&fileMenu.accesskey;">
+       <menupopup id="menu_FilePopup">
          <menuitem id="calendar-new-event-menu"
                    key="new_event_key"
                    label="&event.new.event;"
@@ -129,13 +130,13 @@
                    label="&calendar.print.label;"
                    accesskey="&calendar.print.accesskey;"
                    observes="print_command"/>
-      </menupopup>
-   </menu>
+       </menupopup>
+     </menu>
 
-   <menu id="menu_Edit"
-    label="&editMenu.label;"
-     accesskey="&editMenu.accesskey;">
-      <menupopup id="mppEdit">
+     <menu id="menu_Edit"
+           label="&editMenu.label;"
+            accesskey="&editMenu.accesskey;">
+       <menupopup id="mppEdit">
          <menuitem id="calendar-cut-menu"
                    key="key_cut"
                    label="&calendar.cut.label;"
@@ -166,13 +167,13 @@
                    label="&calendar.selectall.label;"
                    accesskey="&calendar.selectall.accesskey;"
                    observes="select_all_command"/>
-      </menupopup>
-   </menu>
+       </menupopup>
+     </menu>
    
-   <menu id="menu_View"
-    label="&viewMenu.label;"
-     accesskey="&viewMenu.accesskey;">
-      <menupopup id="mppView">
+     <menu id="menu_View"
+           label="&viewMenu.label;"
+           accesskey="&viewMenu.accesskey;">
+       <menupopup id="mppView">
          <menuitem id="calendar-view-menu-day"
                    key="view_day_key"
                    label="&calendar.flat.topbar.dayview;"
@@ -240,13 +241,13 @@
                       label="&calendar.menu.numberofweeks.6;"/>
 	 </menupopup>
 	 </menu>	 
-      </menupopup>
-   </menu>
+       </menupopup>
+     </menu>
    
-   <menu id="menu_Go"
-         label="&goMenu.label;"
-         accesskey="&goMenu.accesskey;">
-      <menupopup id="mppView">
+     <menu id="menu_Go"
+           label="&goMenu.label;"
+           accesskey="&goMenu.accesskey;">
+       <menupopup id="mppView">
          <menuitem id="calendar-go-menu-today"
                    key="go_to_today_key"
                    label="&goTodayCmd.label;"
@@ -267,13 +268,13 @@
                    label="&goNextCmd.label;"
                    accesskey="&goNextCmd.accesskey;"
                    observes="next_command"/>
-      </menupopup>
-   </menu>
+       </menupopup>
+     </menu>
    
-    <menu id="tasksMenu"
-         label="&toolsMenu.label;"
-         accesskey="&toolsMenu.accesskey;">
-      <menupopup id="taskPopup">
+     <menu id="tasksMenu"
+           label="&toolsMenu.label;"
+           accesskey="&toolsMenu.accesskey;">
+       <menupopup id="taskPopup">
          <menuitem id="calendar-wizard-menu"
                    key="wizard_key"
                    label="&calendar.wizard.label;"
@@ -307,14 +308,14 @@
                        label="&preferencesCmd.label;"
                        accesskey="&preferencesCmd.accesskey;"
                        oncommand="openPreferences();"/>
-      </menupopup>
-   </menu>
+       </menupopup>
+     </menu>
 
 
-   <menu id="menu_Help"
-         label="&helpMenu.label;"
-         accesskey="&helpMenu.accesskey;">
-      <menupopup id="menu_HelpPopup">
+     <menu id="menu_Help"
+           label="&helpMenu.label;"
+           accesskey="&helpMenu.accesskey;">
+       <menupopup id="menu_HelpPopup">
          <menuitem accesskey="&releaseCmd.accesskey;"
                    label="&releaseCmd.label;"
                    oncommand="openTopWin('&releaseURL;');"/>
@@ -323,8 +324,8 @@
                    label="&aboutCmd.label;"
                    accesskey="&aboutCmd.accesskey;"
                    oncommand="openAboutDialog();"/>
-      </menupopup>
-   </menu>
-</menubar>
-
+       </menupopup>
+      </menu>
+     </menubar>
+  </toolbaritem>
 </overlay>
diff --git a/calendar/sunbird/base/jar.mn b/calendar/sunbird/base/jar.mn
index 8f1521f784f2..c9ebcf786c63 100644
--- a/calendar/sunbird/base/jar.mn
+++ b/calendar/sunbird/base/jar.mn
@@ -1,3 +1,4 @@
 calendar.jar:
-        content/calendar/calendar.xul                 (content/calendar.xul)
-        content/calendar/menuOverlay.xul              (content/menuOverlay.xul)
+   content/calendar/calendar.xul                 (content/calendar.xul)
+   content/calendar/menuOverlay.xul              (content/menuOverlay.xul)
+*  content/calendar/customizeToolbar.xul         (content/customizeToolbar.xul)