Starting with Xamarin.iOS 6.2.0, assemblies shipped by Xamarin will be signed with a Xamarin key. Prior to this release, the assemblies were either not signed or only delay-signed. This change affects the strongnames of some Xamarin assemblies (Microsoft compatible assemblies strongnames remain unchanged).
Existing user assemblies linking to those assemblies (such as monotouch.dll) should be recompiled using Xamarin.iOS 6.2.0 in order for them to work.
List of changed assemblies for Xamarin.iOS:
Before Xamarin.iOS 6.2.0
MonoTouch.Dialog-1, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
MonoTouch.NUnitLite, Version=0.7.0.0, Culture=neutral, PublicKeyToken=null
OpenTK-1.0, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
OpenTK, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
monotouch, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
Since Xamarin.iOS 6.2.0
MonoTouch.Dialog-1, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065
MonoTouch.NUnitLite, Version=0.8.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065
OpenTK-1.0, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065
OpenTK, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065
monotouch, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065