I don't think Blackberry will like it if Nokia makes a client for BBM.
I also fail to see how Nokia would become unique by making such a client, as it exists on so many Blackberry phones ?
I belive that you missunderstood the request.
He wants Nokia to make a messenger app like the one on Blackberry for Nokia devices. Not that Nokia makes on for RIM
You could try contact Nokia by using the contact options on the website to make your request.
I dont think you will get much response from Nokia at the support forum.
Nokia used to make a BlackBerry Connect client for certain (E-Series?) phones, but discontinued it in favor of other messaging servers like Exchange and Domino. Apparently RIM then announced it would take over development, but I don't think that ever happened. See http://www.bgr.com/2009/01/20/blackberry-support-r