libnet-server-mail-perl 0.17-1 (i386 binary) in ubuntu intrepid

 This module is a versatile and extensible implementation of the SMTP
 protocol and its different evolutions like ESMTP and LMTP. The event
 driven object-oriented API makes easy to incorporate the SMTP protocol
 to your programs.
 .
 Other SMTPd implementations don't support useful ESMTP extensions and
 the LMTP protocol. Their interface design precludes adding them
 later. So I've decided to rewrite a complete implementation with
 extensibility in mind.
 .
 It provides mechanism to easy addition future or not yet implemented
 ESMTP extensions. Developers can hook code at each SMTP session state
 and change the module's behaviors by registering event call-backs. The
 class is designed to be easily inherited from.