Quotes in the Permalink URL

I complained about this a while ago and someone suggested it was being worked on.

If people paste a title from another program into the title field, and if that title contained “smart quotes”, then the quotes turn up in the URL. Why is this the case? The permalink field is great about getting rid of spaces and other bad characters, why do smart quotes (and apostrophes and a few other bad characters) not get filtered out?

Right now I have to go through manually every night and get rid of these, but some times I miss them, resulting in ugly and dysfuntional URLs.

Any progress on this?