problems when compiling C code

Hello,

I would like to call C code from R. My C code is divided in two files. In 
the file "testpermut.c", I have the following lines:

#include "adesub.h"

In my working folder, I have the files:
- adesub.c which contains general functions
- adesub.h with the header of functions contained in adesub.c
- testpermut.c which call some functions defined in adesub.c

When I try to  create my dll (Work on Windows XP, R-1.8.1), I obtain error 
message:

$ Rcmd shlib testpermut.c