I am not sure what is your best option here... I would try either to develop the app in some current distribution and export makefile OR try remote development.
However, chances are also high that C++ compiler on that platform will be so non-conformant that U++ will not compile anyway.... (e.g., it would not compile with 2.95.x GCC and I know there was compiler bug with 3.0.x that kept TheIDE crashing).