See Summary. From Changelog (http://search.cpan.org/src/JASLONG/Mail-DKIM-0.28/Changes): Version 0.18 - released 2006-06-09 * no longer depends on Crypt::RSA or Crypt::OpenSSL::Bignum. Reproducible: Always
Fixed in dev-perl/Mail-DKIM-0.31 (in CVS). Thanks for reporting!