Messages
Forwarding and Replying to Messages

By default, forward messages:
Automatically quote the original message when replying
Then,

Spell check messages before sending

Message Wrapping

Wrap incoming, plain text messages to window width
Wrap outgoing, plain text messages at characters

Send messages that use 8-bit characters

When it's time to clean up messages:
As is (does not work well with some mail servers)
Using the "quoted printable" MIME encoding (does not work well with some mail or newsgroups readers)