option (HoldExpensive) tells
sendmail not to connect to expensive delivery
agents. Instead, mail destined for those agents is queued for later
delivery. This F=e delivery agent flag marks a
delivery agent as expensive.
For example, consider a site connected to the Internet over a
dial-on-demand ISDN link that costs lots of money per minute. Such a
site might want all the Internet mail to be queued and would arrange
for that queue to be processed only once every other hour.
Under V8 sendmail, verbose output (watch
delivery) cancels the effect of the F=e delivery
agent flag (suppresses queueing). Verbose output is
set with the -v command-line switch (-v) or the Verbose option