How to remove a failed spare from an array?

[BjornJentoft]

Proliant ML350 G5, Smart Array E200i.

A spare drive failed, and was replaced with another drive that turned out to be smaller than the original. The status of the physical drive is now as follows:

Status: Failed
Last Failure Reason: Hot plug replacement too small

Since I don't have a big enough drive to replace with, I thought I would just remove the spare from the array all together. This showed to be difficult:

#hpssacli ctrl slot=0 array A remove spares=all

Error: This operation is not supported with the current configuration. Use the
"show" command on devices to show additional details about the
configuration.
Reason: Assignable spares not available

So it boils down to "How to remove a failed spare from an array?".