I may be reading this too quickly, but:
This is a clear pattern of behavior demonstrated by the offender, and there is a clear voluntary ignorance demonstrated by Matt.
Who are you talking about? If someone just rarely sends out PMs and gets turned in, I suggest blocking. If someone is constantly harassing numerous people, I'll do something about it. I don't like enforcing the private message issue, because I don't want to be accused of 'reading' them. However, if someone is a problem, they will get nailed.
That said, who is the user who is sending these PMs?
