Javascript working in firefox but not IE

[Rewire]

This script seems to work fine with firefox but not with IE. It just sets style="display: none" or style="display: " to show / hide submenu items on my menu. I've just tried making it save to a cookie which submenu is currently displayed and reopen that menu on a new page load.

checkCookie() is called onload and switchMenu(menu idhere) when the main menu item is clicked to make the submenu appear. Firefox doesn't display any js errors and reopens the correct menu on a page load whereas IE throws an "object required" error.

function switchMenu(obj) {
var hid = "hide";
    var el = document.getElementById(obj);
    if ( el.style.display != "none" ) {
        el.style.display = 'none';    
        setCookie(hid,1);                
    }
    else {
        el.style.display = '';    
        setCookie(obj,1);    
    }
}
 
 
function setCookie(menuid,expire)
{
var c = "menuid=" + escape(menuid) + ";expires=" + escape(expire);
 //write cookie
document.cookie = c;
}
 
function checkCookie()
{      
 openmenu = getCookie('menuid'); 
if (openmenu != 'hide') {  
   switchMenu(openmenu);   //problem appears to be this line
   }    
   else { switchMenu("hide"); }
}
 
 
 
function getCookie(cookieName) {
 var theCookie=""+document.cookie;
 var ind=theCookie.indexOf(cookieName);
 if (ind==-1 || cookieName=="") return ""; 
 var ind1=theCookie.indexOf(';',ind);
 if (ind1==-1) ind1=theCookie.length; 
 return unescape(theCookie.substring(ind+cookieName.length+1,ind1));
}

[acoder]

Can you also show the menu code.

Is the ID "hide"?