Can I add a subdomain in Cpanel with no conflicts with WPMU?

I have structured WPMU so that every new blog is added as a subdomain. I want to add a membership site outside of the WPMU installation because I want to use Wishlist member and it is not compatible with WPMU.

To do this I want to add the subdomain members.<mysite>.com using CPANEL and not WPMU. Since WPMU is using subdomains, what will happen if someone asks for the the submodan members.<mysite>.com in the future (as I am sure someone might.

1. Will WPMU know that this subdmain is already taken or Will there be a conflict?
2. Is there something I can do to stop this conflict from happening?

I know I can use the Members plugin, but it doesn't have some key functionality that I require.