/*
	Make the overlayer appear, with a background div
*/
function displayOverlayer()
{
	/* Make the div having id 'Background' appear, with an opacity of 0.6 */	
	Effect.Appear("Background", {from: 0.0, to: 0.6, duration: 0});

	/* Make the div having id 'OverlayerDiv' appear, with an opacity of 1.0 */	
   	Effect.Appear("OverlayerDiv", {from: 0.0, to: 1.0, duration: 0});	
   	$('body').style.overflow="hidden";
  	
  	/* Close de frame after 17 sec */
  	setTimeout("closeOverlayer()",17000);
}

/*
	Make the overlayer and its background div disappear
*/
function closeOverlayer()
{
	/* Make the div having id 'OverlayerDiv' disappear */	
   	Effect.Fade("OverlayerDiv", {duration:0});
   	
   	/* Make the div having id 'Background' disappear */	
   	Effect.Fade("Background", {duration:0});
   	$('body').style.overflow="auto";
}