Problem in vertical menu

var menuids = new Array("verticalmenu") //Enter id(s) of UL menus, separated by commas var submenuoffset = -2 //Offset of submenus from main menu. Default is -2 pixels. function createcssmenu() {............................... this is working fine with only one but if i add one more array item i get error var menuids = new Array("verticalmenu,verticalmenu1") //Enter id(s) of UL menus, separated by commas i get error that id is null