Now with DNSSEC!
(NSEC, NSEC3, RSASHA1, RSASHA256, RSASHA512, GOST, ECDSA256 and ECDSA384 from plain zonefiles or replicated databases)

More information & source on the wiki, documentation here
Update! Now part of the PowerDNS Authoritative Server version 3.0, see here. PowerDNS releases can be found from here

Snapshots available from current svn, as Linux packages, as a tarball, tested against BIND, MySQL, PostgreSQL & sqlite3 backends:

$ pdnssec secure-zone powerdnssec.org
$ pdnssec show-zone powerdnssec.org
Zone has NSEC semantics
keys: 
ID = 4 (KSK), tag = 2224, algo = 5, bits = 2048   Active: 1
KSK DNSKEY = powerdnssec.org IN DNSKEY 257 3 5 AwEAAZVtlHc8O4TVmlGx...o/izs68uN2WzqQDZy9Ec2JwBTbxWE=
DS = powerdnssec.org IN DS 2224 5 1 cd79b0d2639aaa5ae5abdc80003836e5e5e0c506
DS = powerdnssec.org IN DS 2224 5 2 706fe0d73ab2658c9efa0d5bfe16d3b3193c902a24806766f38d3749bb5da752

ID = 5 (ZSK), tag = 5985, algo = 5, bits = 1024   Active: 1
ID = 6 (ZSK), tag = 13798, algo = 5, bits = 1024  Active: 0

$ pdnssec import-zone-key powerdnssec.org standard-private-key.private
$ pdnssec deactivate-zone-key powerdnssec.org 4
...
$ pdnssec remove-zone-key powerdnssec.org 4
...
$ pdnssec set-nsec3 '1 0 1 ab' 
$ pdnssec rectify-zone
For more information, please head to the wiki and to the documentation