I saw it earlier today... I added my upvote to sort it out. The only similarities were that both stories had no external urls... they were both questions to the community.

Ah, here it is: http://news.ycombinator.com/item?id=256760

Hmm, sure enough, the submitter is not listed in the voters for that one either. If anyone knows of any other examples, please let me know.

It happened on my last submission. At first I thought I'd been flagged as a spammer, but it still let me vote up manually.

For a day or two my votes didn't count. Maybe they were on moderation when they submitted?

You triggered some automatic protection against some form of abuse. I forget what.

I think that was when I downvoted all the congratulations in your wedding thread. :)