function thumb(screen){
		document.getElementById(screen).style.display='block';
	}
	function thumb_close(screen){
		document.getElementById(screen).style.display='none';
	}

	function show_thumb(img,text){
		var Img_Width =640;
		var Img_Height =479;
		var oWidth	= document.getElementById('body_id').offsetWidth;
		var oHeight	= document.getElementById('body_id').offsetHeight;
		var oLeft	= ((oWidth / 2)-(Img_Width / 2))+"px";
		var oTop	= ((oHeight / 2)-(Img_Height / 2))+"px";
		var div_content = "<a href=\"javascript:thumb_close('show_thumb');\" style=\"position:absolute;right:0;\"><img width=\"28\" height=\"15\" src=\"imgs/x.jpg\" border=\"0\" alt=\"Schließen-Kreuz\" title=\"schließen\" /></a><img src=\"thumbnails/"+img+"\" /><div class=\"caption\">"+text+"</div>";
		document.getElementById('show_thumb').innerHTML = div_content;
		document.getElementById('show_thumb').style.left=oLeft;
		document.getElementById('show_thumb').style.top=oTop;
		document.getElementById('show_thumb').style.display='block';
	}