11gr2 : Dropped table not exists in enabled recyclebin

Hi  ,

Why it's not possible to  find a table dropped with this command :

EXECUTE IMMEDIATE "DROP TABLE EMP1" ;   -- PURGE option is not used !

SQL> SELECT name , value FROM V$parameter WHERE upper(NAME) like '%RECYCLEBIN%';

NAME                                          VALUE

--------------------------------------------- --------

recyclebin                                    on        -- recyclebin is enabled !

select  *  from  dba_RECYCLEBIN rb where upper(rb.object_name) like '%EMP%' or upper(rb.original_name) like '%EMP%' ;

-- no rows

How to restore this table asap ?

Best regards.

GD.