I get this error when I try compiling ( ./configure ) kftpgrabber-0.6.0 on my Vector Linux 10.1 SOHO . Here's what is says next :

you need to install kdelibs first.

If you did install kdelibs, then the Qt version that is picked up by
this configure is not the same version you used to compile kdelibs.
The Qt Plugin installed by kdelibs is *ONLY* loadable if its the
same Qt version, compiled with the same compiler and the same Qt
configuration settings

I do have kdelibs-3.3.2-VL5 installed . Do I need another version or why do I get this error .

did you upgrade kde or qt?

no I did not . everyting concerning KDE & QT si just as it was installed from what I know ( i did not update anyting on purpose )