Problem with disappearing 'counter' for the row number when using pagination

Hello. I've got a problem with disappearing "counter" for the row number. When i click "next or previous" button in pagination, my row counter disappearings. Here is my live example: http://kartoteka.tbop.org.pl/v3/test/dt/examples/server_side/row_details.html . And here info from debugger: http://debug.datatables.net/epesag


This is my js file:

<script type="text/javascript" charset="utf-8">
$(document).ready(function() {
			
oTable = $('#example').dataTable( {
	"fnDrawCallback": function ( oSettings ) {
	     var that = this;
            /* Need to redo the counters if filtered or sorted */
            if ( oSettings.bSorted || oSettings.bFiltered )
            {
                this.$('td:first-child', {"filter":"applied"}).each( function (i) {
                    that.fnUpdate( i+1, this.parentNode, 0, false, false );
                } );
            }
        },
	"bProcessing": true,
	"bServerSide": true,
	"sAjaxSource": "scripts/details_col.php",
	"aoColumns": [
	   { "sClass": "center", "bSortable": false },
		null,
		null,
		null,
       	{ "sClass": "center" },
	{ "sClass": "center" }
	],
	"aaSorting": [[1, 'asc']]
	} );			
	} );
		</script>

This is a part of my php file responsible for the output:

	/*
	 * Output
	 */
	$output = array(
		"sEcho" => intval($_GET['sEcho']),
		"iTotalRecords" => $iTotal,
		"iTotalDisplayRecords" => $iFilteredTotal,
		"aaData" => array()
	);
	
	while ( $aRow = mysql_fetch_array( $rResult ) )
	{
		$row = array();

		/* Add the  details image at the start of the display array */
		$row[]='';

		for ( $i=0 ; $i<count($aColumns) ; $i++ )
		{
			if ( $aColumns[$i] == "version" )
			{
				/* Special output formatting for 'version' column */
				$row[] = ($aRow[ $aColumns[$i] ]=="0") ? '-' : $aRow[ $aColumns[$i] ];
			}
			else if ( $aColumns[$i] != ' ' )
			{
				/* General output */
				$row[] = $aRow[ $aColumns[$i] ];
			}
		}
		$output['aaData'][] = $row;
	}
	echo json_encode( $output );

I think the problem is in the php file - specifically int the row: $row[]=''; Maybe this line override "counters". But when i remove this row, then it's a problem with total number of columns and data don't display.

Sorry for my english

Thanks for help
Greetings
Tom