// JavaScript Document
			function toggleLayer( whichLayer )
			{
			  var elem, vis;
			  if( document.getElementById ) // this is the way the standards work
				elem = document.getElementById( whichLayer );
			  else if( document.all ) // this is the way old msie versions work
				  elem = document.all[whichLayer];
			  else if( document.layers ) // this is the way nn4 works
				elem = document.layers[whichLayer];
			  vis = elem.style;
			  // if the style.display value is blank we try to figure it out here
			  if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined)
				vis.display = (elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none';
			  vis.display = (vis.display==''||vis.display=='block')?'none':'block';
			}