libnet-smtp-server-perl 1.1-6 (i386 binary) in ubuntu eoan

 The Net::SMTP::Server module implements an RFC 821 compliant SMTP
 server, completely in Perl. It's extremely extensible, so adding in
 things like spam filtering, or more advanced routing and handling
 features can be easily handled. An additional module,
 Net::SMTP::Server::Relay has also been implemented as an example of
 just one application of this extensibility. See the pod for more
 details on that module. This extension has been tested on both Unix
 and Win32 platforms.
 .
 Creating a new server is as trivial as:
 .
 $server = new Net::SMTP::Server($host, $port);
 .
 This creates a new SMTP::Server. Both $host and $port are optional,
 and default to the current hostname and the standard SMTP port (25).
 However, if you run on a multi-homed machine, you may want to
 explicitly specify which interface to bind to.