I have a similar situation, but I am using JBoss 4.0.0 and JDK 1.5.0.
and Firebird 1.5.1
My database is created with UNICODE_FSS

If my firebird-ds.xml contains

<config-property name="encoding"
type="java.lang.String">UNICODE_FSS</config-property>

It is OK for Jaybird 1.5.1, but I get NullPointerException for Jaybird
1.5.4 and 1.5.5

If I removed the encoding UNICODE_FSS line from firebird-ds.xml
It is OK for Jaybird 1.5.1 and 1.5.5 (I have not tested for 1.5.4 in
this case)

And I found that my unicode characters works OK without the encoding
UNICODE_FSS in firebird-ds.xml.

Can I continue without the encoding UNICODE_FSS in firebird-ds.xml?
Are there any side effect?

Will there be a fix so that the NullPointerException will not come out
with the line encoding UNICODE_FSS in firebird-ds.xml?

Thanks for the Help.
C. N.