When a Hotspare is configured and not activally replacing another failed disk, it is sitting there doing nothing.  I would think that the Clariion would detect a hotspare that has failed the same way as anyother disk.  I think that the only time it could ever fail is if it was currently in use for a failed drive.  All the other times, it is sitting there idle  After you replace the bad disk that the hotspare disk has fully replaced, you should not get any other errors.  the hotspare disk will go into a "equalizing" state while it copies data back to the replaced disk.  once it is done, it will go "hotspare ready" state.
hello  when a hotspare disk is configured and is in inactive status,  does this disk always keeps writing something?   or is in a standby mode.?  how clariion detect and test  that a hotspare disk is failed, if it is not doing reads and writes?  does it means that there is going to be another failed disk, after replacing the hotspare failed disk with a good one?  mc
cx4 hotspare disk failed or was physically removed - means there is comming 
other failed disk?