var mMenu = document.getElementById("mainMenu").getElementsByTagName("a");
		var mNum = mMenu.length;
		
		for (i=0; i<mNum; i++){
				mMenu[i].name = i;		
					
				mMenu[i].onmouseover = function(){
						for(j=0; j<mNum; j++){
								if(document.getElementById("subMenu"+j)!=null){
										document.getElementById("subMenu"+j).style.display = 'none';	
								}
						}
						if(document.getElementById("subMenu"+this.name)!=null){
								document.getElementById("subMenu"+this.name).style.display = 'block';	
						}
				}
		}