Michael Koch (aka man-di) and Daniel Leidert (as part of the pkg-java team) have worked on packaging the CDK. The ran into some issues, such as the CDK build system not perfectly compatible with the Debian java libraries in /usr/share/java. Both detection of the available libraries as well as putting them in the classpath, caused trouble with the CDBS-based build system wrapping around the Ant build.xml (note the many commit this weekend ;).
The result is noteworthy: CDK has entered the Debian NEW queue. This means that the Debian experts will check that CDK is really ready to enter Debian. Licenses will be checked, for example. This has been one of my long standing wishes, and I am happy that Michael got around to getting things done. Cheers!