CustomDNS is a modular DNS server written in Java. It's based on Brian Wellington's dnsjava pacakge, but it adds support for virtual hostnames, SQL databases, and dynamic client updates. You can use CustomDNS out-of-the-box as a clone of ml.org/dyndns.org, or you can use it to develop custom DNS applications.
Release Notes: Support was added for updating address records through the Web. It's now possible to register a hostname and set the IP address without leaving your Web browser.
Release Notes: A fix for a bug in the server's install process. The server distribution now includes a Perl client, but the Java client still ships by default.
Release Notes: New code to support automatic address dectection when used as a dynamic DNS server, and slight user-interface improvements to the CGIs.