function main_menu_div_change(lay) 
{ 
	if(this.prev_lay){ 
		document.getElementById(this.prev_lay).style.display="none"; 
		document.getElementById(lay).style.display="block"; 
	}else{ 
		document.getElementById(lay).style.display="block"; 
	} 
	this.prev_lay=lay; 
}

function chgimg(obj,im) 
{ 
	obj.src='/Images/_common/menu/'+im+'.gif';
}