How to do folder redirection
Solution 1:
You should be able to do this from within the Group Policy Management Console, inside or outside Server Manager:
http://blogs.technet.com/askds/archive/2008/07/07/installing-gpmc-on-windows-server-2008-and-windows-vista-service-pack-1.aspx
http://trycatch.be/blogs/roggenk/archive/2007/07/25/windows-server-2008-amp-group-policy-management-console-gpmc.aspx
It sounds like the problem you are having is that you have not added the Group Policy Management feature in Server Manager.