Try recompile an reinstall nsjabber passing DB parameter. If i remember well README inside nsjabber tarball has some instructions about this.
Try
make INST=/path/to/your/aolserver DB=2
and
make install INST=/path/to/your/aolserver DB=2
from nsjabber-xxx/bin directory
(DB=2 is for use with postgres, use DB=1 if you want to use it with oracle)
\Orzenil
