Telerik OpenAccess ORM is supporting MVC3 for more than a year. Also there is a sample in Telerik OpenAccess Samples Kit which demonstrates the best practices for integrating Telerik OpenAccess ORM in ASP.NET MVC3 applications.
I hope that helps.
OpenAccess ORM Q3 2013 Beta is available for immediate download in your account. Get it now
and play with the latest bits.