Are you sure it is the same set of arguments? Perhaps one is const and the declaration calls for non-const or vice versa? Try making your own call to the constructor elsewhere (such as in a temporary test.cpp file) and see if that triggers the linker error. Maybe also try gcc2 instead of gcc4, to see if it is a compiler pickiness problem or something else. - Alex I gave it a good stare and it looked OK. It would have been a compile error if there were no matching constructor, right? I will create a toy sample and try that out. I started with gcc2 and switched to gcc4 because of this issue :-) Thanks, Andrew