Time Library added to Playground

I am trying to use the Ethernet shield, and NTP but I'm having problems with the examples out of the box, with the following errors:

heating01.cpp.o: In function write_n(int, int)': C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:133: undefined reference to UdpBytewise'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:133: undefined reference to UdpBytewise' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:133: undefined reference to UdpBytewiseClass::write(unsigned char)'
heating01.cpp.o: In function getUlong()': C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:123: undefined reference to UdpBytewise'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:123: undefined reference to UdpBytewise' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:123: undefined reference to UdpBytewiseClass::read()'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:124: undefined reference to UdpBytewiseClass::read()' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:125: undefined reference to UdpBytewiseClass::read()'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:126: undefined reference to UdpBytewiseClass::read()' heating01.cpp.o: In function sendNTPpacket(unsigned char*)':
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:106: undefined reference to UdpBytewise' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:106: undefined reference to UdpBytewise'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:106: undefined reference to UdpBytewiseClass::begin(unsigned int)' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:107: undefined reference to UdpBytewiseClass::beginPacket(unsigned char*, unsigned int)'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:108: undefined reference to UdpBytewiseClass::write(unsigned char)' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:109: undefined reference to UdpBytewiseClass::write(unsigned char)'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:110: undefined reference to UdpBytewiseClass::write(unsigned char)' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:111: undefined reference to UdpBytewiseClass::write(unsigned char)'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:113: undefined reference to UdpBytewiseClass::write(unsigned char)' heating01.cpp.o:C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:114: more undefined references to UdpBytewiseClass::write(unsigned char)' follow
heating01.cpp.o: In function sendNTPpacket(unsigned char*)': C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:118: undefined reference to UdpBytewiseClass::endPacket()'
heating01.cpp.o: In function getNtpTime()': C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:95: undefined reference to UdpBytewise'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:95: undefined reference to UdpBytewise' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:95: undefined reference to UdpBytewiseClass::available()'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:97: undefined reference to UdpBytewise' C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:97: undefined reference to UdpBytewise'
C:\Users\Stuart\AppData\Local\Temp\build8924192961418854666.tmp/heating01.cpp:97: undefined reference to `UdpBytewiseClass::read()'

Having spent most of the day searching I've turned up nout.. Any help appreciated!

Stuart, newbie..