[kronolith] Sync-problem since update to kronolith 4.2.9 and horde 5.2.7

[Johannes Mock]

Hi

since I updated our horde-server to kronolith 4.2.9 and horde 5.2.7,
thunderbird didn't accept the password for calendar-sync till the
registration. I tried to bind other calendars and tasklist from the
server into thunderbird. I also unsubscribed some of the old calendars
which worked during the last version and rebind them, but nothing works.

Only in the access.log a messege appears:

10.129.0.125 - mockjs [02/Sep/2015:17:34:26 +0200] "PROPFIND
/rpc.php/calendars/mockjs/tasks~7_s4R7Afs-pvnIiSJuZcmw5/ HTTP/1.1" 401
212 "-" "Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101
Thunderbird/38.2.0 Lightning/4.0.2"

Does somebody have a fix for this problem?

Regards
Johannes