How to have a "two section" website? Altering main menu depending on a section

Hi,

We have two major group of users. Home users and Business users.

Two groups have totally different needs.

So I will end up with:

http://www.name.com/link1

http://www.name.com/link2

http://www.name.com/link3

http://www.name.com/business/

http://www.name.com/business/bizlink1

http://www.name.com/business/bizlink2

http://www.name.com/business/bizlink3

My goal is to have two menus (I can configure that in admin panel) that are conditionally shown depending on what section of a website a user is.

Of course we can do it BlackBery[1] style but I don’t think it is not great for us.

Question:

How can make enfold (or WP) show a different main menu depending on the location/section.

Expected result:

A user enters a website and sees a main menu like:

http://www.name.com/link1

http://www.name.com/link2

http://www.name.com/link3

http://www.name.com/business/

Then he clicks http://www.name.com/business/ and menu changes to:

http://www.name.com/business/bizlink1

http://www.name.com/business/bizlink2

http://www.name.com/business/bizlink3

Expected solution:

I know that I can’t make it work using the Enfold interface.

It needs to be coded in a child theme.

What in your opinion is the most elegant and correct way to implement such a solution?

[1] http://us.blackberry.com/business.html?lid=us:bb:business&lpos=us:bb:business

PS. Great theme, love it a lot :)