Sign the dist as the last step before creating the archive. Take care not to modify/regenerate dist meta files or the manifest.

Error: Old SIGNATURE detected. Please inform the module author to regenerate SIGNATURE using Module::Signature version 0.82 or newer. gpg: Signature made Sat 30 Mar 2013 12:27:46 AM JST gpg: using DSA key 1C7229147FE92A42 gpg: Can't check signature: No public key ==> BAD/TAMPERED signature detected! <==

This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.