I use pine for my root acount (system mail) and it keeps one
message in the /var/spool/mail/root file which says not to
delete as it hold configuration for the mail folder.
However, when I log in as root again It says I have meail
when I don't, I just have that message in the mail forlder
that say not to delete!!!!
Mailx checks for mail by looking at the time stamp on the
incoming mail folder. If you wish consistent behavior, then you
will need to use a single mailer consistently. There's no (easy) way
to resolve the conflicting behaviors of pine and mailx.