Thank you every one that is what I was searching for. For the sake of any one searching this in the future here is a short resume of this:
PHP Code:
#include <something>
Will search .inc files in the "include" folder
PHP Code:
#include <something.sp>
wilt search .sp files in the "include" folder
PHP Code:
#include "something.sp"
will search .sp files in the same folder