batv-filter 0.4.0.dfsg-2build1 (armhf binary) in ubuntu raring

 Bounce Address Tag Validation (BATV) is the name of a method, defined in
 Proposed Internet Draft, for determining whether the bounce address specified
 in an E-mail message is valid.
 .
 It is designed to reject backscatter, that is, bounce messages to forged
 return addresses.
 .
 The batv-filter implements both BATV signing and verification.