Security :: Create / Manage Access Rules For Membership Roles Through Code?

I'm using vs 2005 and asp.net 2.0 to create my website. Recently, I thought about applying membership instead of my customized security system in order to achieve higher security level and performance. At first thing went well, since it was easy to create/manage users and Role names from behind code, but when I came upon the "Access Rules" I faced what you can call it an 'obstacle' at least from my opinion.

The thing is, I don't want to use Asp.net Web Site Administration Tool to create and manage my access rules which I'm going to assign to each of my dynamically created Roles. What I want to be able to do is make a page where the Admin can create/manage his desired Role(s) and also, create/manage the Access Rules, then add such Access Rules to the previously created Role(s).

Now, what I need to know first is... is it even possible to do such thing in the first place? Because the way i understand it is, since the access rules are stored in the web.config of each folder/directory that you apply them on then it shouldn't be allowed to modify it from the running/published website.