Right click context menu does not work for table's last row

Hello,

I am seeing an issue where right clicking on the LAST ROW cells of a custom table does not pull up the table's context menu, whereas it does for all other table cells (but the last row). I am creating a custom table using the function below. I am using v2.5 beta 16848. Its erroring out on fck_gecko.js line 66 (char 10927). Any idea whats wrong ? Please help.

FCKWI.SetupTable = function(  oTable, numRows ) {

   var tblBody = '';
   tblBody += '<table border="0" cellspacing="0" cellpadding="0" width="949">';
   tblBody += '<thead><tr>';
   tblBody += '<th class="bp_wi_header bp_firstcol" width="12">Step</th>';
   tblBody += '<th class="bp_wi_header" style="width: 50%;">Action</th>';
   tblBody += '<th class="bp_wi_header" style="width: 50%;">Result</th>';
   tblBody += '</tr></thead><tbody>';
   for (var i=0;i<numRows;i++) {
      tblBody += '<tr><td class="bp_wi_cell bp_firstcol">'
      tblBody += '<strong>' + (i+1) + '.</strong></td>';
      tblBody += '<td class="bp_wi_cell"></td>'
      tblBody += '<td class="bp_wi_cell"></td>'
      tblBody += '</tr>';
   }
   tblBody += '</tbody></table>';
   oTable.innerHTML = tblBody;
   oTable.id = 'workInstruction' ;
}

Thanks