Perl module providing authentication using the Bitcard service

 Authen::Bitcard is an implementation of verification for signatures generated
 by Bitcard authentication. For information on the Bitcard protocol and using
 Bitcard in other applications, see <URL:http://www.bitcard.org/api>
 .
 The module and the protocol are heavily based on Authen::Typekey. (In fact,
 the Bitcard authentication server also supports the TypeKey API!)