Windows phone 8 port failing during build

I'm getting an error at the postproccessing player point of the build:

Error building Player: Exception: Error: type System.Runtime.Serialization.SerializationInfo doesn't exist in target framework. Error: type System.Runtime.Serialization.SerializationInfo doesn't exist in target framework. Error: type System.Runtime.Serialization.SerializationInfo doesn't exist in target framework. Error: type System.Runtime.Serialization.SerializationInfo doesn't exist in target framework. Error: type System.Runtime.Serialization.SerializationInfo doesn't exist in target framework. Error: type System.Runtime.Serialization.SerializationInfo doesn't exist in target framework. Error: type System.ComponentModel.TypeDescriptor doesn't exist in target framework. Error: type System.ComponentModel.TypeDescriptor doesn't exist in target framework.

I am using JsonFx, tk2d, iTween and player prefs.

I scoured the project for anything that might cause this problem, and searched for any references or imports of that type with no luck.