[Alpha] System.PlatformNotSupportedException:This platform is not supported| with Tasks&VS&MonoTouch

Hello,

I'm trying to have Tasks working under Visual Studio 2012 with MonoTouch. I'm using ALPHA channel and have the latest releases installed.

There are 3 projects in solution: 1. PCL (158 target platforms) with async methods 2. Touch 3. Android

This code compiles, could be deployed and executed. But when I make calls from iPhone client:

var asyncResult = await MyClass.DoStuff();
Console.WriteLine("doing stuff completed: " + asyncResult);

I get the following result:

System.PlatformNotSupportedException: This platform is not supported at await part of code. When I write it with Task.ContinueWith - same result.

What is interesting is doesn't work only under Visual Studio + MonoTouch. All other configurations launches this code correctly (WIN+VS+Android, WIN+VS+Android, MAC+XS+iOS, MAC+XS+Android)

Versions of SDK are synchronized with the latest ALPHA release.

Thank you for any suggestions. Alex