@jacekjacek
You can switch the tablet from "blue-pill" to "red pill"-mode (from "safe packages" to "maybe-you-brick-your-tablet-by-installing-this-but-you-want-to-so-we-let-you"-mode, btw. it is a very funny way the change is implemented, search the forum for it if you like ).
Then you can install g++...

@NokmanFive:
http://en.wikipedia.org/wiki/Mono_%28software%29
or
http://www.mono-project.com/Maemo