OK, thanks. Actually no classes are availble from "outside". The Lib has a static class (not a class with static functions but a static implemented class), and only plain functions (that calls member functions of the static class) are available from outside (which prototypes are declared in the .h file that I send to the customer). Does this make it possible to use it from even more compilers? If not, is there perhaps a way to mark these functions as "C" functions? Thanks!