Does JBoss for Linux need to be configured differently than JBoss for Windows for SQLException handling?

Here is my situation: I am creating a Struts 1.1 based application that runs fine under Tomcat 5 and JBoss 3.2.5 on Windows. During login, I am validating the user against their PostgreSQL database login. If they enter a bad username/password, PostgreSQL generates an exception. On Windows the following code works:

catch (SQLException e)
{
log.error("Error in validating user.");
log.error("\tSQL statement = " + sQuery);
log.error("\terror code = " + e.getErrorCode());
log.error("\tstate = " + e.getSQLState());
if (e.getSQLState().equals("08004"))
{
// have a password/userid error, return null user
}

the 'state' is '08004' on userid/password errors.

I packaged up my exploded war directory on Windows and moved it over to Linux and unzipped it into jboss-3.2.5/servers/default/deploy -- same location as on Windows. However when I run the same code on Windows and enter in an invalid user id/passowrd combination, when the exception is thrown and caught and my code is run, the 'state' returned is NULL.

If a proper userid/password are entered they are logged into the system and everything runs fine.

Thanks in advance for any corrections or suggestions.

Brian