When I use Hibernate tool 3.1 beta 4 connect to oracle 10g release 2 in Hibernate configuratation:


!ENTRY org.hibernate.eclipse 2 30000 2006-02-17 20:46:22.810
!MESSAGE WARN Worker-1 org.hibernate.cfg.JDBCBinder - The JDBC driver didn't report any primary key columns in PROXY_DATA$. Asking rev.eng. strategy

!ENTRY org.hibernate.eclipse 2 30000 2006-02-17 20:46:22.850
!MESSAGE WARN Worker-1 org.hibernate.cfg.JDBCBinder - Rev.eng. strategy did not report any primary key columns for PROXY_DATA$

!ENTRY org.hibernate.eclipse 2 30000 2006-02-17 20:46:23.310
!MESSAGE WARN Worker-1 org.hibernate.cfg.JDBCBinder - The JDBC driver didn't report any primary key columns in XDB$ATTRGROUP_REF. Asking rev.eng. strategy

!ENTRY org.hibernate.eclipse 2 30000 2006-02-17 20:46:23.310
!MESSAGE WARN Worker-1 org.hibernate.cfg.JDBCBinder - Rev.eng. strategy did not report any primary key columns for XDB$ATTRGROUP_REF

!ENTRY org.hibernate.eclipse 2 30000 2006-02-17 20:46:23.791
!MESSAGE WARN Worker-1 org.hibernate.cfg.JDBCBinder - The JDBC driver didn't report any primary key columns in V_$WAITCLASSMETRIC. Asking rev.eng. strategy

!ENTRY org.hibernate.eclipse 2 30000 2006-02-17 20:46:23.801
!MESSAGE WARN Worker-1 org.hibernate.cfg.JDBCBinder - Rev.eng. strategy did not report any primary key columns for V_$WAITCLASSMETRIC

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Why?