// Get the value of the cookie with the specified name.
function GetCookie(sName)
{
  // cookies are separated by semicolons
  var aCookie = document.cookie.split("; ");
  for (var i=0; i < aCookie.length; i++)
  {
    // a name/value pair (a crumb) is separated by an equal sign
    var aCrumb = aCookie[i].split("=");
    if (sName == aCrumb[0])
    {
        var crumbValue = aCrumb[1];
        if(crumbValue == null) return null;
        if(crumbValue == "") return null;
        return crumbValue;
    } 
  }

  // a cookie with the requested name does not exist
  return null;
}