vjournal (notes/journal) in general and with davx5

Hello,

does anybody has experience with synchronising the vjournal parts of
kolab?
I always enjoyed the Notes and Journal feature, but since only very few
options exist for really working with them across different clients, I
dont use it anymore and only check once in a while whether there is some
progress.
So, my thoughts are along the line of 
- how do you use notes, journal
- why davx5 doesnt sync it
- which programmes are available at the moment

Recently I stumbled upon a shiny looking android app called 'jtx board'
which relies on davx5 for syncing. However, davx5 only discovers the
calendars and the tasks. 
Since several years I use the very fine android app 'Kolab Notes'. Since
moving away from Korganizer, I havent found another programme to work
with Notes. Someone suggested to sync the vjournal files with
vdirsyncer, but I am having a hard time figuring out the url. Contrary
to tasks and calendars there is no obvious way to display the caldav url
in roundcube.
Since I moved all the vital pim stuff to cli (mutt, khard, khal), I
would love to see something for notes and journal as well.
I also noticed, the Journal part is not even available in roundcube
anymore. However, the folder still exist. There is no button whatsoever
to access Journal.
With davx5 I can create a new caldav ressource with notes/journal
feature set enabled, but in roundcube it doesnt show up in the Notes
section, but as a calendar. Also, it doesnt get picked up by jtx as
notes.

thanks a lot for comments and pointers
Thomas