I think I know what might have happened... The original ping failed back on December 5th 2002, but the ping was re-sent when the blogger republished that entry more recently.
My blogging system does that. I've accidentally re-pinged some blogs occasionally. And I've occasionally had numerous re-pings - and it's usually happened when the blogger is noticably adding updates to the same entry - so I know they have the same issue.
I'm running an old version of MT, and if you don't want the ping to try again, you have to manually uncheck the ping choice, or delete the URL from the "URLs to ping" box, before you save an updated entry. It's very easy to forget to do that, especially if you're just quickly zipping in to correct a typo you caught.