jQuery Grid Plugin - jqGrid

I probably have a strange setup and new to using jqgrid, but what I am attempting to accomplish is to pull into jqgrid an existing html table that contains an imbedded table example:

<table id="someTable">

<thead>

<tr>

<th>colName1</th>

<th>colName2</th>

.......

<th>colNameN</th>

</tr>

</thead>

<tbody>

<tr>

<td>someData1</td>

<td>someData2</td>

.......

<td>someDataN</td>

</tr>

<tr>

<table>

<thead>

<tr>

<td>colName1</td>

<td>colName2</td>

<tr>

<thead>

<tbody>

<tr>

<td>data1</td>

<td>data2</td>

<tr>

</tbody>

</table>

</tr>

</tbody>

</table>

The javascript that I'm attempting to use to display this looks like this

<script type="text/javascript">

jQuery(document).ready(fuction() {

tableToGrid("#someTable")

});

</script>

The above logic displays a table but it appears to be adding the <th> of the inner table to the out table.  Ideally I would perfer to have the inner table as a subgrid.  Is there a way to accomplish this on the client side without having to modify the server side to return back a json object?