Please help on rollback segments!

Today I found that the rollback tablespace and segments were almost full in my oracle server (7.3.4 under NT), which always brings back the error ORA-00604 for my application. I tried to kill all the sessions and hoped that system will free and collect those occupied rollback space, but it didn't work. I also tried to add more data files to the tablespace, and it didn't do any good for my application either. Does anyone know how I can manually clean up those spaces (about 400M)? None of the tables or indexes uses that space. It is just weird how those spaces haven't been released.
Any suggestion will be greatly appreciated! Thanks.
--Jian

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Before you buy. Received on Wed Mar 15 2000 - 00:00:00 CST