ClamWin: Will not scan Real media files

I attempted to scan a single Real media file (.rmvb) and the program sat for a few seconds then brought up the usual scan completed message, only with the number of files scanned and total size of scanned files both listed as 0. It does not seem to have any problem with other file types, and the results are the same when scanning individual files or whole directories. I was using the current version (0.90.2.1) with up to date definitions. It was running from my computer's hard drive in the location to which it was originally extracted, and it was a clean install, not an upgrade.

By the way, I really like the new extraction wizard.