Monkeysphere should use su with "-s /bin/bash"
The following will fail if the monkeysphere user doesn't have a proper shell:
# requote arguments using bash builtin feature (see "help printf"): su "$MONKEYSPHERE_USER" -c "$(printf "%q " "$@")"
For instance when running "monkeysphere-authentication add-identity-certifier" and the monkeysphere user has /sbin/nologin as a shell, we'll get:
This account is currently not available.
A more safer way (that does not expect /bin/bash as shell) would be something like the following:
su -s /bin/bash "$MONKEYSPHERE_USER" -c "$(printf "%q " "$@")"
(from redmine: created on 2014-10-13)