Carbon is a java based SERVER implementation which caters to different server falvors eg: raw data,HTTP, FTP and so on.
Spawning off from Carbon are different server implementations for HTTP/SOCKS proxy, FTP, HTTP, J2EE which are available in a jar.
It can auto test your network setting to connect internet. In China, China Mobile/Unioncom provide two proxy wap gateways to access internet. It used HttpConnection to access network. Source code: http://j2meautonetwork.cvs.sourceforge.net/