Datafile of tablespace with rollback segment lost!

Hi all;

I have accidentally deleted the datafile of a tablespce with contains only a rollback segment...

I try this commands to drop the tablespace:  

STARTUP MOUNT
ALTER DATABASE DATAFILE 'NAME_DATAFILE' OFFLINE DROP ALTER DATABASE OPEN all this is fine, after opening the database I try to drop the tablespace : DROP TABLESPACE 'NAME_TABLESPACE' INCLUDING CONTENTS I have the message
ORA-01548: active rollback segment 'RB_DATA' found,

           terminate dropping tablespace

The rollback segment is nor online or offline, his status is needs recovery !! I can't drop it.

Any help are very appreciated.
Haithem  

   _______       ___________  __
   \      \     /          / / /             Haithem Abdelkefi
    \      \   /          / / /              Vigie Informatique 2000 Inc.
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