The command used was:
svn copy -r 4200 svn+ssh://semor@.../svn/relax/branches/consistency_tests_1.2/
svn+ssh://semor@.../svn/relax/branches/
This is due to a beginner mistake by Sebastien Morin pointed out in the post by Edward d'Auvergne:
https://mail.gna.org/public/relax-devel/2007-12/msg00015.html (Message-id:
<7f080ed10712171508w44f86ee9s813793c246832aeb@...>
The branch will now be ready for merging back into the main 1.2 line...