JDBC : this statement has been closed : postgresql 9

Hi,

I'm having a troube in my application :

org.postgresql.util.PSQLException: This statement has been closed.
at
org.postgresql.jdbc2.AbstractJdbc2Statement.checkClosed(AbstractJdbc2Statement.java:2508)
at
org.postgresql.jdbc2.AbstractJdbc2Statement.getMaxRows(AbstractJdbc2Statement.java:595)
at
org.postgresql.jdbc4.Jdbc4Statement.createResultSet(Jdbc4Statement.java:36)
at
org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler.handleResultRows(AbstractJdbc2Statement.java:211)
at
org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1795)
at
org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
at
org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:500)
at
org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:388)
at
org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:381)
at
org.apache.commons.dbcp.DelegatingPreparedStatement.execute(DelegatingPreparedStatement.java:172)
at
org.apache.commons.dbcp.DelegatingPreparedStatement.execute(DelegatingPreparedStatement.java:172)

It's happen when I execute my PreparedStatement .

Normally it's work well, but in my error log, i found this ....

I'm on ubuntu 10.04 server with a tomcat running.
i Have multi thread running, but i'm sure that other thread can't interfer
with that.

And i'm using this :

<Context>
<Resource name="jdbc/NexessPool"
auth="Container"
type="javax.sql.DataSource"
maxActive="100"
maxIdle="30"
maxWait="20000"
removeAbandoned="true"
removeAbandonedTimeout="120"
username="**********"
password="*********"
driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://localhost/database"
/>
</Context>

which JDBC i'm using ? this one :

http://ejurka.com/pgsql/jars/xml/

from Kris Jurka ( thx to him )

I don't understand why a preparestatement have been close ?

thx for your help,