I have very strange problem with Oracle specific things like OracleResultSet or OraclePreparedStatement: when I try to cast from ResultSet to OracleResultSet, I get ClassCastException.
Problem started when I changed from 3.2.2 to 4.0.0. Everything worked just fine with 3.2.2. Also all basic jdbc things are working, but those Oracle specific things are not. I'm using Oracle 10g thin driver (ojdbc.jar).