Next: How can I sort the messages in my Rmail folder?, Previous: How do I save a copy of outgoing mail?, Up: Mail and news [Contents][Index]
See The Emacs Manual in The Emacs Manual.
(add-hook 'mail-mode-hook 'mail-abbrevs-setup)
Note that the aliases are expanded automatically only after you type a word-separator character (e.g., RET or ,). You can force their expansion by moving point to the end of the alias and typing C-x a e (M-x expand-abbrev).