I was looking at an answer, I went for its revisions and... The Revision#3 looks really strange... I don't have much time to try to investigate what is the reason for that.. But I'd like, because I've never seen other issue like this in SO before.
Firefox 3.6.3 :
Internet Explorer 7:
PS: I suppose this could be an issue generated when decoding from this plain text to html.. Is SO having problems whith some text-formattings?