Setting up obm-conf (2.1.10-0ubuntu2) ...
Not replacing deleted config file /etc/obm/obm_conf.ini
chgrp: cannot access `/etc/obm/obm_conf.ini': No such file or directory
dpkg: error processing obm-conf (--configure):
subprocess installed post-installation script returned error exit status 1
Setting up obm-conf (2.1.10-0ubuntu2) ... obm_conf. ini obm_conf. ini': No such file or directory
Not replacing deleted config file /etc/obm/
chgrp: cannot access `/etc/obm/
dpkg: error processing obm-conf (--configure):
subprocess installed post-installation script returned error exit status 1
This isn't a bug, thus converting to question.