[Boost-users] wave: changing to relative paths in #line output?

I'm evaluating wave as a cpp replacement. I'm having a problem at the moment in that the #line output shows the name of the source file as an absolute path, and my regressions are expecting a gcc-style relative path. Before I have a go at hacking this, can anyone tell me if there's some configuration that can be set to output relative paths? Or to make the output more gcc/cpp-compatible? There are a couple of other minor differences to gcc and mcpp: wave produces '#line n', for example, and the others produce '# n'. Thanks - Paul