Ian writes: "The Beta-2 Release is of JZKit , an open source pure java Z3950 toolkit is now available here  or from sourceforge . JZKit is distributed under the LGPL and supports both origin and target development, but this beta release only features an example client.
The release is aimed at Z3950 developers (It really is for developers only at the moment, and the documentation is almost non-existent) who are interested in a java toolkit and don't mind playing around with beta software. The tookit uses its own internal ASN/BER runtime (Compiler also avialable for download in case you have any pesky private externals, or want to have a go with ISO10161). Right now, the project needs a few interested parties to generate some feedback so we can beat the thing into release shape."