isdnvboxserver 1:3.25+dfsg1-9ubuntu1 (s390x binary) in ubuntu bionic

 Let your Debian system be your answering machine! Messages can be accessed
 remotely, automatically emailed, etc.
 .
 This package provides the vbox server, which must be installed on the
 system with the ISDN card. To actually listen to the recorded messages
 you need the client package (isdnvboxclient) somewhere, not necessarily on
 the same system.