jQuery Grid Plugin - jqGrid

Hi,

The grid's interface displays ok. However, I can't figure out why the error in bold below shows up in Firebug when the data from ajax call returns:

Here is my js code for the grid:

$("#training").jqGrid
(
    {   
        url:'index.php?func=trainingmgr&aAction=loadData',
        datatype: 'json',
        colNames:['Type', 'Title', 'Eff Date', 'Expr Date', 'Href','Status', 'Rec Date', 'Notes'],
        colModel:[{name:'Type', index:'Type', width:55, sortable:true},
                  {name:'Title', index:'Title', width:90, sortable:true},
                  {name:'EffDate', index:'EffDate', width:100, sortable:true},
                  {name:'ExprDate', index:'ExprDate', width:80, align:'right'},
                  {name:'Href', index:'Href', width:80, align:'left'},
                  {name:'Status', index:'Status', width:80, sortable:true, align:'left'},
                  {name:'RecDate', index:'RecDate', width:80, align:'center'},
                  {name:'Note', index:'Note', width:150, align:'left'}],
        rowNum:10,
        rowList:[10,20,30],
        pager: '#pager',
        sortname: 'Type',
        viewrecords: true,
        sortorder: 'asc',
        caption:'Training Manager'
    }   
);
$("#training").jqGrid('navGrid','#pager',{edit:true,add:true,del:true});

And here is the data returned from server for the grid:

stdClass::__set_state(array(
   'page' => 1,
   'total' => 1,
   'records' => 3,
   'rows' => 
  array (
    0 => 
    array (
      'id' => 1,
      'cell' => 
      array (
        0 => 1,
        1 => 'Targeted Recruitment',
        2 => '1/01/2010',
        3 => '1/01/2050',
        4 => 'http://yahoo.com',
        5 => 'Active',
        6 => '2/04/2010',
        7 => NULL,
        8 => 'Recruitment',
        9 => 'Administrator',
      ),
    ),
    1 => 
    array (
      'id' => 2,
      'cell' => 
      array (
        0 => 2,
        1 => 'Transaction Leads',
        2 => '1/01/2010',
        3 => '1/01/2050',
        4 => 'http://google.com',
        5 => 'Active',
        6 => '2/04/2010',
        7 => NULL,
        8 => 'Transactions',
        9 => 'Administrator',
      ),
    ),
    2 => 
    array (
      'id' => 3,
      'cell' => 
      array (
        0 => 3,
        1 => 'Check Email',
        2 => '1/01/2010',
        3 => '1/01/2050',
        4 => 'http://vqck.com',
        5 => 'Active',
        6 => '2/04/2010',
        7 => NULL,
        8 => 'IT',
        9 => 'Administrator',
      ),
    ),
  ),
))

Thank you in advance. This is a great grid by the way.