[horde] TREAN: Editing bookmarks results in error

[Carsten]

Hi everyone,
I found that one on an older bug report, but it never seems to have  
been solved.

"[horde] trean: 404 when deleting or saving after edit"
https://bugs.horde.org/ticket/13743
https://lists.horde.org/archives/horde/Week-of-Mon-20141208/053143.html

I got this "bug",too.
If I edit the bookmark in any way (examble: add a tag) and click on  
"save", I get a
"The requested URL /trean/b/save was not found on this server."

What am I doing wrong or what do I need to correct?

br
Carsten