use Mail::Box::POP3s; my $folder = Mail::Box::POP3s->new(folder => $ENV{MAIL}, ...);
See SYNOPSIS in Mail::Box::POP3
This module mainly extends Mail::Box::POP3.
See DESCRIPTION in Mail::Box::POP3
See Different kinds of folders in Mail::Box
See Available folder types in Mail::Box
See Folder class implementation in Mail::Box
See How POP3 folders work in Mail::Box::POP3