Packages with the dkim use flag

mail-filter / amavisd-new : High-performance interface between the MTA and content checkers

  • Add DomainKeys Identified Mail support

mail-filter / rmilter : Another sendmail milter for different mail checks

  • Enable support for DomainKeys Identified Mail

mail-mta / exim : A highly configurable, drop-in replacement for sendmail

  • Adds support for DomainKeys Identified Mail (DKIM)