function terug()
		{
		history.go(-1)
		}

		function popup_info(url, width, height) {
		var Win = window.open(url,"popup_info",'width=' + width + ',height=' + height + ',scrollbars=1,resizable=1,menubar=0,status=1' );
		}

		function changestates(active_link)
		{
				document.getElementById('link1').className='tabs_inact';
				document.getElementById('link2').className='tabs_inact';
				document.getElementById('link3').className='tabs_inact';
				document.getElementById('link4').className='tabs_inact';
				document.getElementById('link5').className='tabs_inact';
				document.getElementById('link6').className='tabs_inact';			
				document.getElementById(active_link).className='tabs_act';
		}