JDBC: Exception when calling ResultSet.previous()

Hi

In a JAVA-project I need to process a ResultSet with both methods
previous() and next() to move
arround in ResultSets. The ResultSet method next() is no problem. But
when I call the next()
method I get the following exception.

Exception in thread "main" java.lang.AbstractMethodError:
org/postgresql/jdbc1/ResultSet.previous
    at my.postgresqltest.func2(postgresqltest.java:439)
    at my.postgresqltest.func1(postgresqltest.java:276)
    at my.postgresqltest.main(postgresqltest.java:53)


Has anybody a solution to my problem or any ideas ?

Peter