It was built with Asterisk, which enables the game to be played with English words by telephone or Skype. An American telephone number is set up to play the game at 610-332-7236. It is only available in English now, but 45 languages are available to be translated if someone wants to tackle the 542 narrations required for each language. Rich eventually hopes that the game can be used as a foreign language teaching tool.
Asterisk has been used in the past for adventure games ZoIP is a reimplementation of Zork for phones using Asterisk that was first created in 2005. There are phone numbers for connecting to Zork here.