Facebook C# Sdk, Framework 3.5 and Microsoft.Contracts

I've downloaded the Facebook C# SDK. I'm at the point where I have a facebook token and am calling the method:

  var fb = new FacebookClient(token);

I'm getting the following error:

    Could not load file or assembly 'Microsoft.Contracts, Version=1.0.开发者_StackOverflow社区0.0,  
 Culture=neutral, PublicKeyToken=736440c9b414ea16' or one of its dependencies

Any suggestions? I am using the .Net Framework 3.5.

Thanks

The download link is on the right side of the page:

http://msdn.microsoft.com/en-us/devlabs/dd491992