Very interesting! A few comments:
*There are dozens of jars in the source. It will be a huge task to package
those. Would be good to start working on the most important ones that are
not already packaged. I don't think all of them are needed to have a
package with most of the core functionality.
*You need to build-depend(-indep) on exactly one JDK, preferably
java-gcj-compat-dev. Then use one specific JAVA_HOME in debian/rules.
Please read all the developer information on
http://pkg-java.alioth.debian.org .
For comparison, see for example
http://svn.debian.org/wsvn/pkg-java/trunk/dom4j/ .
Regards,
Marcus