Where is the default system-wide configuration file for qpopper?

[Anthony Atkielski]

I give up:  Where is the default system-wide configuration file for
qpopper?  Neither the documentation nor the official Web site ever
specifically identifies it, and even googling for it hasn't helped.
What's the exact path (and the format of entries inside, as the
documentation isn't very clear about that, either)?

-- 
Anthony