No error code on unique constraint violation

Hello,

I'm using postgres-jdbc-80b1.308 (type 3) with Postgres 8 beta 5. I'm
running some unit tests where I test unique constraint violations. When
I get an exception, I check the error code to see what it is and take
appropriate action. With SQL Server and Firebird I get a specific error
code but with the Postgres driver I get 0. I'm not sure if this is a
driver or a Postgres problem.

I'm running on Windows.

L