function start_over()
      	{
        	document.getElementById('navi_start').src = 'fileadmin/sys/grafik/hauptmenue_ro_start.gif';
      	}
      
function start_out()
      	{
        	document.getElementById('navi_start').src = 'fileadmin/sys/grafik/hauptmenue_no_start.gif';
      	}