Comment 2 for bug 68572

I had the same problem and did the following:
- apt-get source postgresql-8.3-pljava-gcj
- debuild...

read readme.html

I had to manually copy pljava.jar into the classpath-folder, since the binary-package didn't contain this file.

Added the following entries in postgresql.conf (as described):
custom_variable_classes = 'pljava' # list of custom variable class names
pljava.classpath='/usr/share/postgresql-8.3-pljava/pljava.jar'

so, now it work's