category name in SEO URLs

The "must read" on Duplicate Content is this article on the official Google Webmaster Central blog:

http://googlewebmastercentral.blogspot.com/2008/09/demystifying-duplicate-content-penalty.html

Specifically: "But most site owners whom I hear worrying about duplicate content aren't talking about scraping or domain farms; they're talking about things like having multiple URLs on the same domain that point to the same content. Like www.example.com/skates.asp?color=black&brand=riedell and www.example.com/skates.asp?brand=riedell&color=black. Having this type of duplicate content on your site can potentially affect your site's performance, but it doesn't cause penalties."

In other words, there is no issue: Google understands that both product pages (with and without the keyword rich URL) point to the same content, that you were not trying to trick anyone, that it is simply that your Web site loads the same content in a couple of different ways, and that there is no issue on your Web store.

The same thing would happen if you had a hard-coded search link (e.g. to load products between $50 and $100) that loads the same list of products as a category. In that case too, nothing to worry about.

So being on iis6 and using the 404 handler it can be done so we wont lose our url's already indexed by the search engines.

Does this require that the servor be on IIS 7.

My question is simple:

When we upgrade to version 4.0 and activate isapi is there a means to do a 301 redirect for all of the indexed pages in the search engines so we don't lose our indexing they have already done on our old url's

Will that be the same for the product details page as well with a -000.htm