Can't insert more than 80 registers!?

Hi! My first post.
I have a problem that's getting crazy. I'm going to discriminate what I used to
get a better understanding.

Tools used:
-----------
Postgres 7.4.2
JDBC

Drivers tested (all downloaded from Postgres site):
---------------------------------------------------
pg74.1jdbc2.jar
pg74.213.jdbc2.jar
pg74.213.jdbc3.jar

Table (DDL):
------------
CREATE TABLE PLANO_ENSAIO (
id INT8 NOT NULL
, ensaio_fk INT8 NOT NULL
, op_fk INT8 NOT NULL
, data_hora TIMESTAMP(10) NOT NULL
, estado CHAR(1) NOT NULL
, user_id CHAR(10) NOT NULL
, dt_hr TIMESTAMP(10) NOT NULL
, PRIMARY KEY (id)
, CONSTRAINT plano_ensaio_fk FOREIGN KEY (ensaio_fk) REFERENCES ENSAIO
(id)
, CONSTRAINT plano_ensaio_op_fk FOREIGN KEY (op_fk) REFERENCES OP (id)
);

NOTE:
I compiled Postgres server without any tweaking.

Here's the testing code:

Class.forName("org.postgresql.Driver");
Connection conn =
DriverManager.getConnection("jdbc:postgresql://localhost:6543/dbdev",
"developer", "xpto");

Statement st = null;
for(int i = 1; i <= 90; i++) {
st = conn.createStatement();
st.executeUpdate("INSERT INTO
plano_ensaio(id,ensaio_fk,op_fk,data_hora,estado,user_id,dt_hr) VALUES (" + i +
",1,1,'2004-04-04 10:11:11','A','mike','2004-05-05 05:55:55')");
}

st.close();
conn.close();

Results:
The code above doesn't give any error. The BIG problem is that it's only
inserting 80 and NOT 90 registers!?
I've tried everything I know and I can't get it working.
I thought it could be because of some WAL configuration, so I increased the
"wal_buffers" parameter, but got no success.

Can someone please help me? Don't know what to do.
--
Adira j ao Net Dialup Light. Acesso profissional gratuito.
NovisNet, a Internet de quem trabalha. http://www.novisnet.pt