title: jqgrid multiselect issue
body: <p>I am having a strange issue with jqgrid. when i select a row, row gets selected but checkbox is not getting checked and also when i select another row, previous rows does not get unselected rather its just keep adding to selection. so plzz help....</p>
  
  <pre><code> $("#list9").jqGrid({
                  url: '/Home/DynamicGridData/',
                  datatype: 'json',
                  mtype: 'GET',
                  colNames: ['Report', 'Download'],
                  colModel: [
            { name: 'Name', index: 'Name', width: 610, align: 'left' },
            { name: 'Download', index: 'Download', width: 300, align: 'left', sortable: false, formatter: LinkFormatter}],
                  pager: jQuery('#pager9'),
                  rowNum: 10,
                  rowList: [5, 10, 20],
                  sortname: 'Name',
                  sortorder: 'asc',
                  recordpos: 'left',
                  viewrecords: true,
                  loadonce: true,
                  multiselect: true,
                  caption: 'Docs Library',
                  onSelectRow: function (rowid) {
  
                  }
              });
  </code></pre>