code: public static Object getProperty(Stanza packet, String name) {
          Object res = null;
          JivePropertiesExtension jpe = (JivePropertiesExtension) packet.getExtension(JivePropertiesExtension.NAMESPACE);
          if (jpe != null) {
              res = jpe.getProperty(name);
          }
          return res;
      }
docs: Convenience method to get a property from a packet. Will return null if the stanza contains
  not property with the given name.
  
  @param packet
  @param name
  @return the property or <tt>null</tt> if none found.