How to mark dbspace "down"

Hi folks, I am evaluating OnBar in Online 7.22, generally it seems OK - as easy as ontape to use and in most cases it works. However , if a non-critical dbspace is not down, it does not allow to do warm restore - says - " Excuse moi, the dbspace is up and I am not going to run restore on it" Now , I have a non-critical dbspace (i.e dbspace which is not rootdbs and does not contain logical or phys logs). It consists of one chunk, which is cooked file for simplicity. Mirroring is disabled in this instance. I create some dummy database in this dbspace, populate with some data and then create level 0 archive ( onbar -b -w ). Then I do something nasty : say delete this chunk on Unix level ( yeap, just rm) or corrupt it : banner " I'll be back.Schwarz"> /my/poor/chunk . After that I do all sort of things to assure Online that something bad has just happened: force checkpoints, run onchecks, bring the instance down and up, etc. Online marks the chunk down, but it thinks that the dbspace is perfectly well, though this bleeding dbspace consists of only one chunk,which is terminally ill. Therefore I stiil cannot do warm restore for this dbspace, only full (cold) restore is possible. Are there any sure ways to tell Online that a dbspace is down? All ideas will be appreciated. Cheers Ilya