mh-alias-local-users

mh-alias-local-users is a variable defined in `mh-e.el'.
Its value is

t

Documentation:
*Non-nil means local users are added to alias completion.

Aliases are created from "/etc/passwd" entries with a user ID
larger than a magical number, typically 200. This can be a handy
tool on a machine where you and co-workers exchange messages.
These aliases have the form "local.first.last" if a real name is
present in the password file. Otherwise, the alias will have the
form "local.login".

If you're on a system with thousands of users you don't know, and
the loading of local aliases slows MH-E down noticeably, then
turn this option off.

This option also takes a string which is executed to generate the
password file. For example, use "ypcat passwd" to obtain the
NIS password file.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 7.1 of the MH-E package that is part of Emacs 22.1.