function getCookieValue (cookieName)
{
   var cookieValue = document.cookie;
   var cookieStartsAt = cookieValue.indexOf(" " + cookieName + "=");
   if (cookieStartsAt == -1)
   {
	cookieStartsAt = cookieValue.indexOf(cookieName + "=");
   }
   if (cookieStartsAt == -1)
   {
	cookieValue = null;
   }
   else
   {
	cookieStartsAt = cookieValue.indexOf("=", cookieStartsAt) + 1;
    	var cookieEndsAt = cookieValue.indexOf(";", cookieStartsAt);
	if (cookieEndsAt == -1)
	{
	   cookieEndsAt = cookieValue.length;
  	}
	cookieValue = unescape(cookieValue.substring(cookieStartsAt,cookieEndsAt));
   }
   return cookieValue;

}

function delete_cookie (cookie_name)
        {
	       var cookie_date = new Date ();
	       cookie_date.setTime (cookie_date.getTime() - 1);
	       document.cookie = cookie_name + "=; expires=" + cookie_date.toGMTString() + ";path=/;";
    
	       	
        }