Free space overwrite causes stream of Windows errors

Just tested out this new feature and got a stream of error messages like the following:

Windows - Delayed Write Failed

Windows was unable to save all the data for the file C:\$BitMap. The data has been lost. This error may be caused by a failure of your hardware on network connection. Please save this data elsewhere.

This was followed by error after error with just the filename in the message changing (went on to System32 files after that), had to do a forced shutdown as they just kept coming. Luckily was running under Recuva so no damage done. Don't know if the fact I tested under Recuva was the reason for the above but thought it was worth mentioning just in case.

(WinXP SP3)