LDA versus LMTP

[Steve Matzura]

On Thu, 11 Jun 2015 15:14:31 -0400, Ajai Khattri <symbiat at gmail.com>
wrote:

>Im using Dovecot for LMTP for all my mail users, since this way they are
>completely virtual (i.e. dont need to have a local account at all), all
>mail gets delivered to Maildirs owned by dovecot. Also LMTP makes it easier
>to insert scripts and do any custom processing which presumably is where
>Sieve comes in. Its also pretty easy to setup.

Sounds like that's what I should be doing. OK, so how is Dovecot told
to use LMTP instead of LDA? I must not be understanding something
about what's in either 15-lda.conf or 20-lmtp.conf.