After the new packages are installed, the groupware and admin process needs a restart:

$ /etc/init.d/open-xchange-groupware restart
$ /etc/init.d/open-xchange-admin restart

NOTE: Please take care, that you do not restart Open-Xchange during the process where it updates it's database. A database update can happen after installing minor or major updates. As soon as the first user tries to log in to the system or if any provisioning action is done, this update starts.