Enabling tcpwrappers

[kepa]

Hi all,

I would like use Dovecot with tcpwrappers enabled to control remote 
access using hosts.deny and hosts.allow.

A google search gave this response from the listserve, but it is several 
years ago:

http://www.dovecot.org/list/dovecot/2013-April/089455.html

Are these instructions for configuring the conf files still valid? Mainly:

/etc/dovecot/dovecot.conf

login_access_sockets = tcpwrap

conf.d/10-master.conf:

service tcpwrap {
    unix_listener login/tcpwrap {
      group = $default_login_user
      mode = 0600
      user = $default_login_user
    }
}

Also:

Which version of Dovecot at least is needed to enable tcpwrappers?

Does the tcpwrap option need to be enabled during configure and build or 
is it already (and enabled in any distro binary repositories)?

And is it dovecot, imap, or imaps in the hosts.allow/deny file as the 
service name?

Thanks!

Kepa