connect by prior - error

Hi guru's

I read in manual as "the connect by clause should not have a subquery".

to test it, i tried in the following manner, but why the session disconnects from the session?

SQL> select level
  2 from emp
  3 start with mgr is null
  4 connect by prior
  5 empno in (select mgr from emp);
select level
*

ERROR at line 1:
ORA-03113: end-of-file on communication channel

SQL> select * from emp;
select * from emp
*

ERROR at line 1:
ORA-01041: internal error. hostdef extension doesn't exist

SQL> regards,
Nirmal.

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
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Author: Nirmal Kumar  Muthu Kumaran
  INET: NIRMALK_at_qtel.com.qa

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