configure cannot find KDE headers

Hello, does someone know who to tell a configure script where to find the KDE headers? When I try to compile a certain KDE application, configure fails with the following error: [...] checking for KDE... configure: error: in the prefix, you've chosen, are no KDE headers installed. This will fail. So, check this please and use another prefix! I have the following KDE devel packages installed: - kdebase-kde3-dev - kdelibs-kde3-dev Am I missing any package? I tried the prefix returned by "kde-config --prefix": ./configure --prefix=/opt/kde3 But the error remains the same. Do you have any ideas? Regards, Stefan