Commented Issue: Doesn't hook up to MVC ApiControllers [7116]

Hi,

I'm trying to use fluent validation for my MVC 4 WebApi project.
But it only seems to work on controllers that are inherited from the Controller type.

When I use MyController : Controller -> works fine (ModelState.IsValid returns False)
but when I use MyController :ApiController ... nothing.

How can I make this work on the WebApi ?
Comments: Please provider the documentation how to install as a model validator provider for Web API.