jQuery Grid Plugin - jqGrid

I'm having a problem getting data with getCell.  Maybe it's just me doing something wrong, but I don't see it.

I have the following grid defined:

  $("#grid").jqGrid({
    datatype: "local",
    height: 208,
    colNames:['Id', 'Process','Description','Parent','Tier','Affected','Active'],
    colModel:[
      {name:'id', index: 'id', sortable: false, hidedlg: true, hidden: true },
      {name:'process', index:'process', width:125 },
      {name:'description',index:'desc', width:300},
      {name:'parent',index:'parent', width:125 },
      {name:'tier',index:'tier', width:60, align:"right",sorttype:"int"},
      {name:'affected',index:'affected', width:60, align:"right" },
      {name:'active',index:'active', width:60, align:"right" }
    ],
    multiselect: false,
    hidegrid: false,
    forceFit: true,
    caption: "Processes",
    onSelectRow: grid_onSelectRow
  });

Example row data:

    {id:"93",process:"GPM",description:"CRM/GPM",parent_id:"12",parent:"Distribution",tier:"1",affected:true,active:true},

I have a function defined to handle the "onSelectRow" event:

  function grid_onSelectRow( rowid, status )
  {
    alert( rowid + ": " + status );
    var contents = $("grid").getCell(rowid, "id");
    alert( contents );
  }

but the final "alert" always displays "false". Incidentally, the first alert always displays the row number (1-6) and "true".

What am I doing wrong?