strange error

Hi all....

    I am running a small jdbc program and i get an error like this...


[sriram@nmlinux2 sriram]$ java jdbc
Internal error: caught an unexpected exception.
Please check your CLASSPATH and your installation.
java/lang/NoSuchMethodError: java/sql/Statement.getResultSetConcurrency()I
        at org.postgresql.jdbc2.Connection.getResultSet(Connection.java:216)
        at org.postgresql.core.QueryExecutor.execute(QueryExecutor.java:121)
        at org.postgresql.Connection.ExecSQL(Connection.java:398)
        at org.postgresql.jdbc2.Statement.execute(Statement.java:130)
        at org.postgresql.jdbc2.Statement.executeQuery(Statement.java:54)
        at jdbc.main(jdbc.java:18)
Aborted


i am able to connect to the database with ease.
my jdbc:18 is the line PreparedStatement ps=con.prepareStatement("SELECT.....");

what could be the error or where should i ammend my code


thanks