the majority of what you are looking for is in the microchip librarys
Look throught this url link:
http://ww1.microchip.com/downloads/en/DeviceDoc/MCHP_App_Lib_v2010_08_04_Installer.zip after downloading browse to project :
C:\Microchip Solutions\TCPIP Demo App
In file: TCPIPConfig.h
and then uncomment this line #define: STACK_USE_UART2TCP_BRIDGE
In the meanwhile, prepare to do some reading.
their is also a newer library dated 19-10-2010 , although i have not looked through the code , i would presume it will be the same
file layout
hope this helps