Problem on including an archive library with ProjectCenter

[Copland]

Hi,

I try to port a "Tool" program from Mac OS X to GNUstep that uses some
external libraries as GLPK (GNU Library Linear Programming Kit). I
recompiled the library on GNUstep that give me a "libglpk.a" file. I
put this file in the project directory and add it as a library in
ProjectCenter. Know, when I build the project, I get the error message
"glpk.h: No such file or directory". However, the file is considered in
the GNUmakefile generated by ProjectCenter (testTool_TOOL_LIBS +=
-lglpk). Are there anyone to help me ?

Thanks a lot