title: panel viewport missing scrollbar in ie extjs
body: <p>I've the following Extjs code that works fine in FF but in IE a vertical scrollbar does not appear when overflow happens in west region. Whats wrong?</p>
  
  <pre><code>Ext.onReady(function(){
  
     var viewport = new Ext.Viewport({
          layout:'border',
          items:[{
              region:'west',
              id:'west-panel',
              split:true,
              width: 250,
              minSize: 175,
              maxSize: 400,
              collapsible: false,
              margins:'5 0 5 5',
              cmargins:'5 5 5 5',
      border: false,
              autoScroll:true,
      layout:'fit',
              layoutConfig:{
          autoWidth:false
              },
              contentEl:layers
          },{
              region:'center',
              margins:'5 5 5 0',
              layout:'column',
              autoScroll:false,
      border: false,
              contentEl:main
              }]
      });
  
  });
  </code></pre>