diff --git a/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/NamespaceTests.cs b/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/NamespaceTests.cs
index 9b622095af..42d41eca2f 100644
--- a/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/NamespaceTests.cs
+++ b/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/NamespaceTests.cs
@@ -1,7 +1,9 @@
 // Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
 // This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
 using System;
+using System.Windows;
 using System.Windows.Controls;
+
 using NUnit.Framework;
 
 namespace ICSharpCode.WpfDesign.Tests.Designer
@@ -105,6 +107,18 @@ namespace ICSharpCode.WpfDesign.Tests.Designer
 	
 	public class CustomButton : Button
 	{
+		public static readonly DependencyProperty TestAttachedProperty = DependencyProperty.RegisterAttached("TestAttached", typeof(double), typeof(CustomButton),
+		                                                                                                     new FrameworkPropertyMetadata(Double.NaN));
+
+		public static double GetTestAttached(UIElement element)
+		{
+			return (double)element.GetValue(TestAttachedProperty);
+		}
+
+		public static void SetTestAttached(UIElement element, double value)
+		{
+			element.SetValue(TestAttachedProperty, value);
+		}
 	}
 	
 	public class CustomCheckBox : CheckBox
@@ -116,6 +130,18 @@ namespace ICSharpCode.WpfDesign.Tests.Controls
 {
 	public class CustomButton : Button
 	{
+		public static readonly DependencyProperty TestAttachedProperty = DependencyProperty.RegisterAttached("TestAttached", typeof(double), typeof(CustomButton),
+		                                                                                                     new FrameworkPropertyMetadata(Double.NaN));
+
+		public static double GetTestAttached(UIElement element)
+		{
+			return (double)element.GetValue(TestAttachedProperty);
+		}
+
+		public static void SetTestAttached(UIElement element, double value)
+		{
+			element.SetValue(TestAttachedProperty, value);
+		}
 	}
 	
 	public class CustomCheckBox : CheckBox
@@ -127,6 +153,18 @@ namespace ICSharpCode.WpfDesign.Tests.OtherControls
 {
 	public class CustomButton : Button
 	{
+		public static readonly DependencyProperty TestAttachedProperty = DependencyProperty.RegisterAttached("TestAttached", typeof(double), typeof(CustomButton),
+		                                                                                                     new FrameworkPropertyMetadata(Double.NaN));
+
+		public static double GetTestAttached(UIElement element)
+		{
+			return (double)element.GetValue(TestAttachedProperty);
+		}
+
+		public static void SetTestAttached(UIElement element, double value)
+		{
+			element.SetValue(TestAttachedProperty, value);
+		}
 	}
 	
 	public class CustomCheckBox : CheckBox
diff --git a/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/SetPropertyTests.cs b/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/SetPropertyTests.cs
index c1ad04f4f9..374648181d 100644
--- a/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/SetPropertyTests.cs
+++ b/src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/Designer/SetPropertyTests.cs
@@ -3,6 +3,7 @@
 
 using System;
 using System.Windows;
+using System.Windows.Controls;
 using System.Windows.Data;
 using System.Windows.Markup;
 
@@ -47,5 +48,29 @@ namespace ICSharpCode.WpfDesign.Tests.Designer
 			button.Properties.GetProperty("Content").SetValue("Hello World!");
 			AssertCanvasDesignerOutput("<Button Width=\"100\" Height=\"200\" Content=\"Hello World!\" />", button.Context);
 		}
+		
+		[Test]
+		public void SetAttachedProperties()
+		{
+			DesignItem button = CreateCanvasContext("<Button />");
+			
+			button.Properties.GetAttachedProperty(Grid.ColumnProperty).SetValue(0);
+			button.Properties.GetAttachedProperty(CustomButton.TestAttachedProperty).SetValue(0);
+			button.Properties.GetAttachedProperty(ICSharpCode.WpfDesign.Tests.Controls.CustomButton.TestAttachedProperty).SetValue(0);
+			button.Properties.GetAttachedProperty(ICSharpCode.WpfDesign.Tests.OtherControls.CustomButton.TestAttachedProperty).SetValue(0);
+			
+			AssertCanvasDesignerOutput("<Button Grid.Column=\"0\" t:CustomButton.TestAttached=\"0\" sdtcontrols:CustomButton.TestAttached=\"0\" Controls0:CustomButton.TestAttached=\"0\" />",
+			                           button.Context,
+			                           "xmlns:sdtcontrols=\"http://sharpdevelop.net/WpfDesign/Tests/Controls\"",
+			                           "xmlns:Controls0=\"clr-namespace:ICSharpCode.WpfDesign.Tests.OtherControls;assembly=ICSharpCode.WpfDesign.Tests\"");
+		}
+		
+		[Test]
+		public void SetInstanceProperty()
+		{
+			DesignItem button = CreateCanvasContext("<Button />");
+			button.Properties.GetProperty("Width").SetValue(10);
+			AssertCanvasDesignerOutput("<Button Width=\"10\" />", button.Context);
+		}
 	}
 }