screenshot from another editor, posted at https://en.wikipedia.org/wiki/File:Date_tangling.png
The exact/elapsed timestamps are displaying on top of each other, in various browsers.
(definitely a problem in IE7. Possibly also a problem in older versions of Chrome, though this appears to be resolved in the code currently at ee-flow. Monobook skin might be a factor in some cases.)
It has been seen in timestamps for posts on a board, and for timestamps in topic-history pages (2nd screenshot).
Reporting on behalf of users at https://en.wikipedia.org/wiki/Wikipedia_talk:Flow#Feedback_on_timestamp_bug