When you launch minicom from the gnome-panel (programs>internet>minicom) it
launches, but merely flashes a terminal window. Attempting to launch
minicom from the command line results, of course, in the error:
minicom: there is no global configuration file /etc/minirc.dfl
Ask your sysadm to create one (with minicom -s).
A configuration similar to rp3-config would probably be appropriate (asking
for root's password to run the configuration), or simply adding a default
global configuration file.
That indeed is a slight inconvenience. It isn't a bug though. I've
changed the severity to "Enhancement" as that fits better. I won't
guarantee anything, but it is a possible future enhancement.