ext multi select

[[WP]joju]

 var msForm = new Ext.form.FormPanel({
        title: 'MultiSelect Test',
        width:700,
        bodyStyle: 'padding:10px;',
        renderTo: 'multiselect',
        items:[{
            xtype:"multiselect",
            fieldLabel:"Multiselect<br />(Required)",
            name:"multiselect",
            dataFields:["code", "desc"], 
            valueField:"code",
            displayField:"desc",
            width:250,
            height:200,
            allowBlank:false,
            data:[[123,"One Hundred Twenty Three"],
                ["1", "One"], ["2", "Two"], ["3", "Three"], ["4", "Four"], ["5", "Five"],
                ["6", "Six"], ["7", "Seven"], ["8", "Eight"], ["9", "Nine"]],
            tbar:[{
                text:"clear",
                handler:function(){
	                msForm.getForm().findField("multiselect").reset();
	            }
            }]
        }]
})

can i add this multi select to my coolite window? im having an "object required" javascript error when i do so, please help, im adding this through the scriptManager.Listeners.DocumentReady.Handler