ppp 2.4.4b1-1ubuntu3 (amd64 binary) in ubuntu dapper

 The Point-to-Point Protocol (PPP) provides a standard way to transmit
 datagrams over a serial link, as well as a standard way for the machines
 at either end of the link (the "peers") to negotiate various optional
 characteristics of the link. Using PPP, a serial link can be used to
 transmit Internet Protocol (IP) datagrams, allowing TCP/IP connections
 between the peers.