[wplug] IMAP revisited... to send mail?

[Brandon Kuczenski]

... Maybe I'm just missing something incredibly obvious, but how does one
configure an IMAP server for *sending* mail?  None of the docs seem to
talk about this.  It seems to me that the IMAP server wouldn't have
anything to do with *sending* mail, anyway -- but now that I have the
*checking* mail part working just fine, I'm realizing that the other half
of the equation isn't there.

Is this an issue that I have to solve by configuring the MTA? (which is
postfix, in this case)  Or what?  Is that what this mysterious "SASL" is
about?  And how is that different from "SSL"?

Sometimes I feel just hopeless about this stuff.

-Brandon