how to hide drop Table in Cat list in oracle 10g

New Command of Oracle 10g:

Purge is useful in oracle 10g when you want to really truly drop a table in oracle 10g table can be undropped. for example in sql
SQL> desc t;
it show name type etc   x     null      varchar2(2000)      now you want to drop this table by
SQL> drop table t;
table dropped.
SQL> desc t;
object  t does not exist ;
SQL> flashback table t to before drop;
flashback complete.
SQL> desc t;
show table  t like   x    null   varchar2(2000)
SQL> select object_name from recyclebin;
object_name   Bin$totcup302.... after flashback

Now everything you drop a table, we just hide it not really drooped same with index etc.
SQL>drop table t purge;
table drooped and not show in object list.