function selectAll( cbName )
{
   for( j=0; j < document.forms.length; j++ ) {
      for( i=0; i < document.forms[j].elements.length; i++ ) {
         if( document.forms[j].elements[i].type == "checkbox"
          && document.forms[j].elements[i].name == cbName )
         {
            document.forms[j].elements[i].checked = true;
         }
      }
   }
}

function deSelectAll( cbName )
{
   for( j=0; j < document.forms.length; j++ ) {
      for( i=0; i < document.forms[j].elements.length; i++ ) {
         if( document.forms[j].elements[i].type == "checkbox"
          && document.forms[j].elements[i].name == cbName )
         {
            document.forms[j].elements[i].checked = false;
         }
      }
   }
}

function invertSelection( cbName )
{
   for( j=0; j < document.forms.length; j++ ) {
      for( i=0; i < document.forms[j].elements.length; i++ ) {
         if( document.forms[j].elements[i].type == "checkbox"
          && document.forms[j].elements[i].name == cbName )
         {
            if( document.forms[j].elements[i].checked == true )
               document.forms[j].elements[i].checked = false;
            else
               document.forms[j].elements[i].checked = true;
         }
      }
   }
}