code: protected int loadExpires(Scriptable cfg) {
  		int expires = 0;
  		Object oExpires = cfg.get(EXPIRES_CONFIGPARAM, cfg);
  		if (oExpires != Scriptable.NOT_FOUND) {
  			try {
  				expires = Integer.parseInt(toString(oExpires));
  			} catch (NumberFormatException ignore) {
  				throw new IllegalArgumentException(EXPIRES_CONFIGPARAM+"="+oExpires); //$NON-NLS-1$
  			}
  		}
  		return expires;
  	}
docs: Initializes and returns the expires time from the server-side
  config JavaScript
  
  @param cfg
  The parsed config JavaScript as a properties map
  @return the expires time