During connection lifetime, user is allowed to mark
specific message (one or more) as deleted. This means that
after that it is not listed and no information about that
message should be visible to end user. Still, since each
message has it's own index visible to user, deleting
message during connection would break those indexes and
they would change. For that reason, as long as user
doesn't send 'QUIT' command message is still
available (just marked as deleted). When 'QUIT' is
issued, Pop3 server will fire UpdateMailbox
event where you should check each message, and purge from
mailbox (or delete from folder) ones that are deleted.
Even if user deletes some message during session, he
still has option to 'undelete' them using
'RSET' command. For this reason, you should not try
to track deleting of messages during session because you
might get 'out of sync'. Rather, use regular
UpdateMailbox event.
Deleted
Property
