Well, theres a reason they're "back"; they never where gone...
Keep in mind that there are 2 parties in a PM, not just one. So when one person deletes, it's still there for the other user, until they delete the message as well.
There where two differant ways to go about pm importing:
A. Don't import them, gone forever.
B. Import all pm's and assign them to the users who had posted in them.
Seeing as most users use pm's, we all harassed rick till he went with B :x...
And you could purge pm's by using the datestamp and a unix epoch date...
