jQuery Grid Plugin - jqGrid

I want to create multiple jqgrid in the side loop.jqgrids create as expected with different div ids

I create common funtion to create grid and pass necessay paramiters to create jqgrids as follows

<s:iterator id="formNodeId" status="formNode" value="formDTO.formNodes">

    <s:set name="metaNodeId" value="#formNodeId.metaNodeId" />
    <s:set name="displayLegend" value="#formNodeId.displayLegend" />
    <s:set name="cardMax" value="#formNodeId.cardMax" />
    <s:set name="result" value="#formNodeId.tableColumnView" />

  <s:url value="/integrator/main/searchTableGridForm?id=%{#formNodeId.id}" var="dataUrl" />

<script type="text/javascript">   
                
    // pass parameters to create jqgrid in side loop

         
   createTableView('grid_<s:property value="#metaNodeId"/>','pager_<s:property value="#metaNodeId"/>','<s:property   value="#metaNodeId"/>','<s:property value="#displayLegend"/>','<s:property value="#result"/>','<s:property value="#dataUrl"/>');

        </script>

  </s:iterator>   

function createTableView(ajaxId,pagerid,metaNodeId,displayLegend,result,gridModel){

    $('#'+ajaxId).jqGrid('GridUnload');

 $('#'+ajaxId).jqGrid({
                 url: gridModel,
                 datatype: 'json',
                 pager: '#'+pagerid,
                 loadtext: "Loading…",
                 mtype: 'GET',
                 colNames: getJSonObject(result).column,                     
                 colModel: colData,
                 postData: {           
                  },
                 rowNum:20,
                    rowList:[20,40,60],
                    height: '100%',
                    autowidth: true,
                 rownumbers: true,              
                    sortname: 'id',
                 viewrecords: true,
                 sortorder: "asc",
                 caption:displayLegend,
                 emptyrecords: "Empty records",
                 loadonce: false,
                 loadComplete: function() {
                 },               
                 jsonReader : {
                         root: ""+displayLegend+"",
                         page: "page",
                         total: "total",
                         records: "records",
                         repeatitems: false,     
                         id: "0″     
                     }
              }); 

}

The problem is that jqgrid doesn't change postdata params!

I'm mean ,the results is always equals the first one.

when I check request parameters in side server it pass same request parameters allong with url gridModel

example

when i sent 3 request with following urls

<s:url value="/integrator/main/searchTableGridForm?id=590″ var="dataUrl" />

<s:url value="/integrator/main/searchTableGridForm?id=500″ var="dataUrl" />

<s:url value="/integrator/main/searchTableGridForm?id=503″ var="dataUrl" />

String metanodeId=request.getParameter("id");

when I retrieve request parameters it's duplicate parameter for each request

log.debug(" ####################  search() : " + id);

####################  search() :  590

####################  search() :  590

####################  search() :  590