Despite the webmaster's lack of response, I will post the requested change here for forum users. The webmaster can take a hike as far as I care now.
This topic was discussed and confirmed in this topic
http://forum.arduino.cc/index.php?topic=184523.0
EthernetUDP.stop() should be added to the reference docs.
public:
EthernetUDP(); // Constructor
virtual uint8_t begin(uint16_t); // initialize, start listening on specified port. Returns 1 if successful, 0 if there are no sockets available to use
virtual void stop(); // Finish with the UDP socket