function nOverTab(tag,num){
    if(num==0){return; }
	for(i=1; i <5; i++){
		if (i == num)
		{
			tag.className = "active"; 
			document.getElementById("subnavcon"+i).style.display = "block";
		}else{
			document.getElementById("mainnavcon"+i).className = "normal"; 
			document.getElementById("subnavcon"+i).style.display = "none";
		}
	}
}