在配置中定义的ASP MVC 5.0 RoleProvider中的Unity依赖注入

I'm trying to implement a role provider using a separate EF repository class, as an injectable dependency, to access my roles store. My problem is that the role provider is defined in configuration (web.config) and therefore is not instantiated via the Unity DI container. I haven't been able to find a way to either shift the configuration to code or get hold of the role provider after it's built to call container.BuildUP() on it. Any suggestions would be appreciated. I'm trying to implement a role provider using a