function changeImages() {
	if (document.images) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

function mOvr(src,clrOver) {
  if (!src.contains(event.fromElement)) {
	src.style.cursor='hand' ;
	src.bgColor = clrOver ;
  }
}

function mOut(src,clrIn) {
  if (!src.contains(event.toElement)) {
	src.style.cursor='default' ;
	src.bgColor = clrIn ;
  }
}

isIE = (document.all && document.getElementById) ? true : false;
isNS4 = (document.layers) ? true : false;
isNS6 = (!document.all && document.getElementById) ? true : false;


function show(block) {
	
	if(isIE) {

		document.all.about.style.visibility="hidden";
		document.all.professional.style.visibility="hidden";
		document.all.events.style.visibility="hidden";
		document.all.ims.style.visibility="hidden";
		document.all.contact.style.visibility="hidden";

		document.all[block].style.visibility="visible";
	
		}
	
	if(isNS4) {
	    
		document.layers["about"].visibility="hidden";
		document.layers["professional"].visibility="hidden";
		document.layers["events"].visibility="hidden";
		document.layers["ims"].visibility="hidden";
		document.layers["contact"].visibility="hidden";
	
		document.layers[block].visibility="visible";
	
		}
	
	if(isNS6) {
	 
	 	document.getElementById("about").style.visibility="hidden";
	 	document.getElementById("professional").style.visibility="hidden";
	 	document.getElementById("events").style.visibility="hidden";
	 	document.getElementById("ims").style.visibility="hidden";
	 	document.getElementById("contact").style.visibility="hidden";
	
		document.getElementById(block).style.visibility="visible";
		}
}


function hide() {
	
	if(isIE) {
		document.all.about.style.visibility="hidden";
		document.all.professional.style.visibility="hidden";
		document.all.events.style.visibility="hidden";
		document.all.ims.style.visibility="hidden";
		document.all.contact.style.visibility="hidden";
		}
	
	if(isNS4) {
	    
		document.layers["about"].visibility="hidden";
		document.layers["professional"].visibility="hidden";
		document.layers["events"].visibility="hidden";
		document.layers["ims"].visibility="hidden";
		document.layers["contact"].visibility="hidden";
	
		}
	
	if(isNS6) {
	 
	 	document.getElementById("about").style.visibility="hidden";
	 	document.getElementById("professional").style.visibility="hidden";
	 	document.getElementById("events").style.visibility="hidden";
	 	document.getElementById("ims").style.visibility="hidden";
	 	document.getElementById("contact").style.visibility="hidden";
		}
}