Both for Blend Preview for Silverlight 5 and VS designers fails at any RuleFor (but at runtime everything works perfectly):
Method not found: 'System.Delegate System.Reflection.MethodInfo.CreateDelegate(System.Type, System.Object)'.
at System.Dynamic.Utils.TypeExtensions.CreateDelegate(MethodInfo methodInfo, Type delegateType, Object target)
at System.Linq.Expressions.Compiler.LambdaCompiler.CreateDelegate()
at System.Linq.Expressions.Compiler.LambdaCompiler.Compile(LambdaExpression lambda, DebugInfoGenerator debugInfoGenerator)
at System.Linq.Expressions.Expression`1.Compile()
at FluentValidation.Internal.PropertyRule.Create[T,TProperty](Expression`1 expression, Func`1 cascadeModeThunk) in c:\Projects\FluentValidation\src\FluentValidation\Internal\PropertyRule.cs:line 124
at FluentValidation.AbstractValidator`1.RuleFor[TProperty](Expression`1 expression) in c:\Projects\FluentValidation\src\FluentValidation\AbstractValidator.cs:line 115
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