ExtendedDataModel and rowKeyVar problem

[supernovasoftware.com]

I switched to ExtededDataModel and have it working nicely. Previously my rowKeyVar was incrementing with each row.

My current implementation is using a primary key for the this apparently.

How can I access the row number as it is rendered? I do this so my mouseover can restore the orginal color of the row onRowMouseOut.

<rich:dataTable id="pipeSearchDataTable"
 var="pipeSummary"
 value="#{pipeSearchExtendedDataModel}"
 styleClass="f_table"
 rowClasses="tr0,tr1"
 rows="20"
 rowKeyVar="rowNum"
 onRowMouseOver="this.className='trMouseOver'"
 onRowMouseOut="this.className='tr#{rowNum % 2}'">