I created a new Silverligh 4 solution and am using Nuget to configure it for Catel, using the Microsoft Package Manager (In the extension manager it only finds one reference to Catel 2.1).
Catel.Core installed just fine. Catel.Silverlight on the other hand results in an error:
PM> Install-Package Catel.Silverlight
'SilverlightToolkit-Core (≥ 4.2010.4)' not installed. Attempting to retrieve dependency from source...
Successfully installed 'SilverlightToolkit-Core 4.2010.4'.
Successfully installed 'Catel.Silverlight 2.2'.
Installing code snippets for Visual Studio 2005
Installing code snippets for Visual Studio 2010
Install failed. Rolling back...
Install-Package : Unable to find assembly references that are compatible with the target framework '.NETFramework,Version=v4.0'.
At line:1 char:16
+ Install-Package <<<< Catel.Silverlight
+ CategoryInfo : NotSpecified: (:) [Install-Package], InvalidOperationException
+ FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PowerShell.Commands.InstallPackageCommand