drop flashback archive gets ora-600

 hello,

How drop FDA ? is there an explication ?

I am testing FDA feature on my 11.1.0.6 on Xp.

so, I would like drop my FDA flash1, but I can't. I get an ORA-600 :

SQL> select FLASHBACK_ARCHIVE_NAME, LAST_PURGE_TIME, status
  2  from dba_flashback_archive;

FLASHBACK_ARCHIVE_NAME
--------------------------------------------------------------------------------

LAST_PURGE_TIME
---------------------------------------------------------------------------
STATUS
-------
FLASH1
25/09/09 17:12:47,000000000

SQL> select count(*) from dba_flashback_archive_tables;

  COUNT(*)
----------
         0

SQL> drop flashback archive flash1;
drop flashback archive flash1
*
ERREUR Ó la ligne 1 :
ORA-00600: code d'erreur interne, arguments : [12811], [75582], [], [], [], [],
[], []

SQL>