@TinkerWorX that link shows how to make a call to an unmanaged fastcall function, but it isn't very flexible (i.e. it requires preparing the assembler code for the function parameters you are dealing with) - no idea if it actually works either :P
@spazzarama, Yeah, calling isn't actually the issue. The problem I see is that I can't mark my methods with the fastcall convention. I think what I need is something that translates from fastcall to stdcall then calls the hook method and then converts back from stdcall to fastcall before returning control.