narval #2060065 narval-bot not installable when cubicweb is not running [waiting feedback]

This

 apt-get -uVf install cubicweb-apycot narval-apycot
 [snip]
 Setting up cubicweb-apycot (2.1.1-1) ...
 Setting up narval-bot (3.0.6-1) ...
 insserv: Service cubicweb has to be enabled to start service narval
 insserv: exiting now!
 update-rc.d: error: insserv rejected the script header
  dpkg: error processing narval-bot (--configure):
subprocess installed post-installation script returned error exit status 1
 configured to not write apport reports
                                     dpkg: dependency problems prevent configuration of narval-apycot:
narval-apycot depends on narval-bot; however:
 Package narval-bot is not configured yet.
 dpkg: error processing narval-apycot (--configure):
dependency problems - leaving unconfigured
 configured to not write apport reports
                                     Processing triggers for python-support ...
 Processing triggers for menu ...
 Processing triggers for python-central ...
 Errors were encountered while processing:
 narval-bot
 narval-apycot
  E: Sub-process /usr/bin/dpkg returned an error code (1)
prioritynormal
typebug
done in<not specified>
closed by<not specified>