ext rowexpander控件在ie8下出现异常，但在火狐切可以正常显示求问题怎么解决

小弟想用rowexpander控件在gridpanel下显示信息，但点击+号时，就可以看到其余的信息，但是在ie8上出现如下提示：
消息: 参数无效。
行: 7
字符: 30678
代码: 0
URI: cis21.shinyv.com/administrator/extjs3.3/ext-all.js小弟刚学，不知道怎么回事，望高手、有经验的解救。感激不尽。网页错误详细信息
火狐下正常：ie下报错
找找了多逗号的地方 也没有多写逗号。
代码：
var sm = new Ext.grid.CheckboxSelectionModel();
            var col=new Ext.grid.ColumnModel([sm,new Ext.grid.RowExpander({
                   remoteDataMethod : this.getMyStuff
            }),{header:'ID',dataIndex:'id',sortable: true},
                                              {header:'内容标题',  dataIndex:'title',sortable: true},
                                              {header:'评论内容',dataIndex:'comment',sortable: true},
                                              {
                                                 header: '审核状态', dataIndex: 'isExamine', renderer:changeCommentFormate,editor:new Ext.form.ComboBox({
                                                     triggerAction:'all',
                                                     mode:'local',
                                                     editable:false,
                                                     store:new Ext.data.ArrayStore({
                                                         fields:['partakeOption','partakeValue'],
                                                         data:[['审核通过',1],['未审核',0],['审核未通过',2]]
                                                     }),
                                                     displayField:'partakeOption',
                                                     valueField:'partakeValue'
                                                 }),sortable: true
                                              },{header:'加精', dataIndex:'type',width:50,renderer: function (v) {
                                                     if(v==0){return '否';}else{return '是';}
                                                 },sortable: true},                  
                                              {header:'IP', dataIndex:'ip',sortable: true},
                                              {header:'用户名',dataIndex:'releaser',sortable: true},
                                              {header:'时间',dataIndex:'release_time',sortable: true}
                                            
                                          ]);
this.grid = new Ext.grid.GridPanel({
                    id:'commentLists',
                    viewConfig : {// 实现列自动填充满表格的宽度
                        forceFit : true
                    },
                    enableColumnMove : false,
                    stripeRows : true,
                    validateOnBlur:false,
                    sm:sm,
                    plugins: new Ext.grid.RowExpander({
                          remoteDataMethod : this.getMyStuff
                    }),  //定义插件
                    colModel:col,
                    store:this.store,
                    autoScroll: true,
                    view: new Ext.grid.GridView({
                        forceFit: true,
                        Dirty: false
                    }),
                    selModel : new Ext.grid.RowSelectionModel({
                        singleSelect : true
                    }),
                    bbar : new Ext.shinyv.PagingToolbar({pageSize:20,store:this.store}),
                    tbar:this.tbar
            
            });
getMyStuff:function (_grid,record,index){
            //alert(_grid+","+record.id+","+index);
            var _flag=1;
            MyColumnTree = Ext.extend(Ext.ux.tree.ColumnTree, {
                videoPropertyFormPanel: null,
                constructor : function() {
                    MyColumnTree.superclass.constructor.call(this, {
                         rootVisible:false,
                        autoScroll:true,
                        width:3000,
                       // autoWidth:true,
                        renderTo: 'remData' + index,
                        border : false,
                        validateOnBlur:false,
                        style : "padding:5 5 5 40px",
                
                        root: new Ext.tree.AsyncTreeNode({
                            text:'Tasks'
                        }),
                        columns:[{
                            dataIndex:'id'
                            
                           // width:150
                          
                        },{width:220},
                        //{
                       //     width:150,
                      //      align : 'center',
                      //      dataIndex:'displayName'
                     //   },
                        {
                            dataIndex:'comment',
                            width:120
                         },
                        {
                              dataIndex:'isExamine',
                              width:120,
                              renderer: function (v) {
                             if(v==0){return '未审核';}
                             else if(v==1){return '审核通过';}
                             else{return '审核未通过';}
                         }},
                        {
                                 dataIndex:'type',
                                 width:120,
                                 renderer: function (v) {
                             if(v==0){return '否';}else{return '是';}
                         }},
                         {
                             dataIndex:'ip',
                             width:120
                          },
                        {
                              dataIndex:'releaser',
                              width:120
                         },
                        {
                             dataIndex:'release_time',
                             width:120
                         }
                        ],
                
                        loader: new Ext.tree.TreeLoader({
                            uiProviders:{
                                'col': Ext.ux.tree.ColumnNodeUI
                            }
                        }),
                        
                        listeners : {
                                "beforeload" : {
                                    fn : function(_node){
                                        this.loader.dataUrl = 'index2.php?option=com_shinyv_comment&json=1&task=getList&id='+record.id+'&treeId='+_node.id;
                                        scope : this
                                }
                            }
                        }
                        
                    });
                }
                
            });
            var tree=new MyColumnTree();
            tree.expandAll(); // 展开所有结点
            },大神帮忙看看 到底什么什么问题。小弟不胜感激、  在线等。 火狐IE8ExtJS异常控件