I've followed this hint to get the local KDE version out of
kded4 --version and it shows
Qt: 4.8.7 KDE Development Platform: 4.14.16 KDE Daemon: 4.14.16
But the Info-Center (as suggested here) do show different versions - and probably the right ones.
How can that happen? My first and maybe naive guess is, that kded4 shows actually its own version:
kdelibs-bin amd64 4:4.14.16-0ubuntu3.1 [167 kB]