Oracle JDBC driver problem?

[Dato Yuan]

When i run the follow code:

...
PreparedStatement ps ... 
ParameterMetaData pmd = ps.getParameterMetaData();
...

use driver:classes12.jar throw exceptin

java.lang.AbstractMethodError: oracle.jdbc.driver.T4CPreparedStatement.getParameterMetaData()Ljava/sql/ParameterMetaData; 
...

use jdbc14.jar throw exceptin

at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:125) 
        at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:162) 
        at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:227) 
        at oracle.jdbc.driver.DatabaseError.throwUnsupportedFeatureSqlException(DatabaseError.java:537) 
        at oracle.jdbc.driver.OraclePreparedStatement.getParameterMetaData(OraclePreparedStatement.java:9086) 
        at org.apache.commons.dbcp.DelegatingPreparedStatement.getParameterMetaData(DelegatingPreparedStatement.java:212) 
....

the same code can pass test when i use sybase12.5,with jconn3.jar...