extjs1 grid 表头添加checkbox列

[发哥1997]

刚接手的项目用到了extjs，extjs的版本是1.xx的。表格内容是用xml配置，具体如下，现在想在标题头部添加一个checkbox，请教下，有哪位大神接触过，万望指点迷津1

<?xml version="1.0" encoding="UTF-8"?>
<grid>
<editable>false</editable>
<EditModel>
<insert>false</insert>
<modify>false</modify>
<remove>false</remove>

</EditModel>

<EventModel>
<events>
<event>
<name>rowcontextmenu</name>
<handler>
function(grid,rowIndex,e) {
}
</handler>
</event>
<event>
<name>rowdblclick</name>
<handler>
function(grid,rowIndex,e) {
}
</handler>
</event>
</events>
</EventModel>

<PagingModel>
<size>15</size>
</PagingModel>

<ColumnModel>
<uppercase>true</uppercase>
<columns>

<column>
<isId>true</isId>
<name>CFG_MANAGER_ID</name>
<label>CFG_MANAGER_ID</label>
<hidden>true</hidden>
<locked>true</locked>
<editable>false</editable>
<xlsExportAble>false</xlsExportAble>
</column>
<column>
<name>ID</name>
<label>选择</label>
<align>center</align>
<xlsExportAble>false</xlsExportAble>
<width>5%</width>
<render>
<![CDATA[
return '<input id="'+record.get('ID')+'" type="checkbox" style="width: 10px;height: 10px;"/>';
]]>
</render>
</column>

<column>
<name>MANAGER_END_TIME</name>
<label>查看历史</label>
<width>15%</width>
<align>center</align>
<xlsExportAble>false</xlsExportAble>
<sortable>true</sortable>

</render>
</column>
</columns>
</ColumnModel>
<DataModel>
<proxy>dwr</proxy>
<expr>PfmNewConfigService.queryLeadManagerForList</expr>
</DataModel>
</grid>