title: Using fnRender with ajax source datatable
body: <p>I was trying just modifying one of the examples to do customize a cell:</p>
  
  <pre><code>var oTable = $('#example').dataTable( {
                  "bProcessing": true,
                  "sAjaxSource": "sources/deep.txt",
                  "aoColumns": [
                      { "mDataProp": "engine" },
                      { "fnRender": function( oObj ) {
                                      return "Test";
                                  } },
                      { "mDataProp": "platform.inner" },
                      { "mDataProp": "platform.details.0" },
                      { "mDataProp": "platform.details.1" }
                  ]
              } );
  </code></pre>
  
  <p>Which uses a source like:</p>
  
  <pre><code>{ "aaData": [
  {
      "engine": "Trident",
      "browser": "Internet Explorer 4.0",
      "platform": {
          "inner": "Win 95+",
          "details": [
              "4",
              "X"
          ]
      }
  },
  ...
  ...
  </code></pre>
  
  <p>Data is displayed correctly but I started getting "DataTables warning (table id = 'example'): Requested unknown parameter '1' from the data source for row 0"</p>
  
  <p>Anything I'm missing? Or I should be doing this in a different way?</p>