public static FastDateFormat getInstance
        (String pattern, DateFormatSymbols symbols)
        throws IllegalArgumentException
    {
        return getInstance(pattern, null, null, symbols);
    }
@param pattern {@link java.text.SimpleDateFormat} compatible pattern
@param symbols optional date format symbols, overrides symbols for
system locale
@return the fast date format
xmppserver/src/main/java/org/jivesoftware/util/FastDateFormat.java