BioBytes Messages: 285 Registered: October 2008 Location: France
After exploring your files and Pgsql include and libray files you use in your project, I realized that you compile your project using MingW. If I am right you should have a libpq.a file in your PostgreSQL lib directory.
I prefer to use MySql and MSC15 in my projects. You will find attached a libpq.a file I got from psgsql 9.1 version I guess. Maybe it could help on your side.