The member xxx is not recognized or is not accessible.

[janos]

I consider this a buggy behavior, but maybe somebody will explain that:

Lets have a class derived from UserControl and defining properties Language
and Target.

MainWindow.xaml uses this construct:
<i:MyClass x:Name="..." Language="..." Target="..."/>

Works fine in Visual Studio.

Expression Blend (v3) shows two problems:
1. Reports unrecognized/non-accessible property (bug)
2. Becomes mal-functioning and sooner ot later crashes (lousy programming)

Cause of the problem:
Property Language is defined in the base class, too. Blend apparently finds
the base class implementation and then looks for other properties in the base
class, too. (Bug)

Resolution:
Renaming the property to avoid the name conflict.