function SwitchMenu(obj){
var element = document.getElementById(obj);
var navElements = document.getElementById("section_nav").getElementsByTagName("ul");

	if(element.style.display != "block"){ 
		for (var i=0; i<navElements.length; i++){
			if (navElements[i].getAttribute("id") == null || navElements[i].getAttribute("id") == "") {
				navElements[i].style.display = "block";
			}else if (element.getAttribute("id").indexOf("sub") >= 0){				
				var parentID = element.parentNode.parentNode.getAttribute("id");								
				element.parentNode.parentNode.style.display = "block"; 
				var subNavElements = document.getElementById(parentID).getElementsByTagName("ul");				
				for (var subNavI=0; subNavI<subNavElements.length; subNavI++){
					if (subNavElements[subNavI].getAttribute("id") != element.getAttribute("id")){						
						subNavElements[subNavI].style.display = "none";
					}else{
						subNavElements[subNavI].style.display = "block";
					}
					
				}
			}else if (navElements[i].getAttribute("id") != element.getAttribute("id")){								
				navElements[i].style.display = "none";				
			}
		}			
		element.style.display = "block";
	}else{			
		element.style.display = "none";			
	}	
}