The EZB dismissed the server address "rzblx1.uni-regensburg.de"
So I just did put a new version online that uses the new address
"ezb.uni-regensburg.de" throughout the project.
Everything should work fine now again.
PS: if you run a local installation, I would recommend to use the latest
revision 127 from SVN
svn co https://doctor-doc.svn.sourceforge.net/svnroot/doctor-doc/trunk