fud - provide information about user mailboxes
FUD is a long lived datagram daemon started from inetd that provides information about when a user last read their mail, when mail last arrived in a user's mailbox, and how many messages are recent for that user.
Though not really a bug, FUD will silently ignore any requests that it does not consider valid.
FUD is an experimental interface meant to provide information to build a finger-like service around. Eventually it should be superceded by LDAP or ACAP (using the mailbox dataset).