Last modified: 2006-06-24 13:08:58 UTC
I don't know how many people realize this, and I don't know how risky it is to file it as a bug, but purging the caché (or editing it without making any changes) of a user talk page will fire a message alert. If a troll were to get ahold of this and write a script, it would be rather annoying and we would never know who it was (without access to the server log, anyway). A message alert should only be triggered if there is actually a change in the text of the page.
Unable to reproduce with a regular action=purge, but the null edit thing *does* trigger the new talk flag.
...and should now be corrected in SVN trunk, r14996.