Oh, I should of mentioned that the installed name is 'arm-linux-' followed by the tool name, such as gcc or g++. So to compile the helloworld.cpp file for pre-2.6 firmware, this should work:
Code:
arm-linux-g++ helloworld.cpp
If you get 'arm-linux-g++: command not found', install 'g++-arm-linux-gnueabi'. I can't remember if the g++ compiler is installed with the gcc one.