While at it, nuke /etc/GNUstep/GNUstep.conf and reinstall gnustep-make as well.
It seems I was accidentally trying to build a newer version of GNUstep that I had on the test bed a while ago (and forgot about it). I found an apparently older tree in a different location and rebuilt everything including make. This got me going again.
The beast was looking for the back bundle in /usr/GNUsteo and who knows where. I have everything in /opt/GNUstep.
Anyway, thanks for all the useful info!!
Best wishes,
Andreas