title: jQgrid subgrid - bad grid or cur is undefined error
body: <p>This is the second day I am struggling with this issue, it seems either no one is using subgrid or I am peeweeing something here.</p>
  
  <p>This is my grid code:</p>
  
  <pre><code>    jQuery("#gridTable").jqGrid({ 
          url: ROOT + '/admin/station/getPagedList.json',
          datatype: "json", 
          jsonReader : {
              cell: "",
              id: "0", 
              repeatitems: false,
      //      subgrid: { 
      //           root:"rows", 
      //           repeatitems: false, 
      //           cell:"cell" 
      //        } 
              },
          colNames:['ID', 'Esta&amp;ccedil;&amp;atilde;o', 'Sigla', 'Linha', 'Lote', 'Empresa'], 
          colModel:[ 
                    {name:'id',index:'id', width:50, editable:false, hidden: true}, 
                    {name:'name',index:'name', width:130, editable:true}, 
                    {name:'acronym',index:'acronym', width:35, editable:true}, 
                    {name:'line.name',index:'line.name', width:130, editable:true}, 
                    {name:'line.lot.name',index:'line.lot.name', width:130, editable:false}, 
                    {name:'line.lot.company.name',index:'line.lot.company.name', width:130, editable:false}, 
          ], 
          subGrid : true,
          subGridUrl: ROOT + '/admin/contact/getList.json',
          subGridModel: [{
              name : ['Nome','Contato'],
              width : [150, 150] 
          }],
          rowNum:30, 
          rowList:[30,50,75], 
          pager: '#pager', 
          sortname: 'name', 
          viewrecords: true, 
          imgpath: ROOT + '/css/jquery/cptm/images',
          caption:'Esta&amp;ccedil;&amp;otilde;es', 
          height:"auto",
          altRows:true,
          altclass:"jqgrow-alt",
          loadError : function(xhr,st,err) {
              if (xhr.status.toString() == '901') {
                  jAlert('Sua sess&amp;atilde;o expirou.&lt;br&gt;Por favor efetue o login novamente.', 'AVISO', function(){
                      location.href = ROOT + "/logout";
                  });
              }
          },
      });
  </code></pre>
  
  <p>I have already tweaked the subgrid URL to return several variances of Json but this is the most far I got:</p>
  
  <p>{"rows":[{"cell":"0987654321"}]}
  <img src="https://i.stack.imgur.com/oiGQu.png" alt="Each character of the cell element works like a column"></p>
  
  <p>Someone please help me.
  @Oleg, take a look if you can please.</p>