Commercial mapping service that does route optimization

I am doing some contract work and the company I'm working for wants a feature integrated in their product that does route optimization. So for instance, if given a set of addresses in the U.S. (or possible internationally later), and a start point it would tell the driver to go to this address, this address etc.. and then back to the start point in the optimal order. I realize this is the infamous "travelling salesman problem"- but is there any mapping services anyone knows about that will solve these kind of problems?

I know that there are some consumer mapping software programs that claim to be able to optimize a route w/as many as 99 waypoints, but I take it you're looking for something more corporate-oriented, robust, and fully supported (ever try to call M$ about MapPoint? HA!)?