Some magazine on the newststand just had a review of this gun. I read it 2 weeks ago. It may still be on the news stand, but it might have already been picked up.
Anyway, in the magazine review, they mentioned a smith who specializes in altering this gun. See if you can still find that article.
It was also mentioned on the Beretta forum. Try posting a new message for someone to give you the info from that article...