I ran into a strange issue; there's a question (How do I get from an instance of a class to a Class object in ActionScript 3?) that is fairly old (October 15th, 2008) that I found useful. I've never voted on it before, but when I tried to vote it and its answer up, I got "Vote too old to be changed, unless this question is edited". That seems to be wrong; I haven't ever seen this question before (and notably the vote arrows don't indicate that I've ever voted on it).
This is occurring with svn revision: 5620.