diff --git a/src/Main/Base/Project/Src/Gui/Pads/PropertyPad/PropertyContainer.cs b/src/Main/Base/Project/Src/Gui/Pads/PropertyPad/PropertyContainer.cs
index 65f7821887..ff455cb872 100644
--- a/src/Main/Base/Project/Src/Gui/Pads/PropertyPad/PropertyContainer.cs
+++ b/src/Main/Base/Project/Src/Gui/Pads/PropertyPad/PropertyContainer.cs
@@ -40,8 +40,10 @@ namespace ICSharpCode.SharpDevelop.Gui
 		/// </summary>
 		public PropertyContainer()
 		{
-			PadDescriptor desc = WorkbenchSingleton.Workbench.GetPad(typeof(PropertyPad));
-			if (desc != null) desc.CreatePad();
+			if (WorkbenchSingleton.Workbench != null) {
+				PadDescriptor desc = WorkbenchSingleton.Workbench.GetPad(typeof(PropertyPad));
+				if (desc != null) desc.CreatePad();
+			}
 		}
 		
 		object selectedObject;
diff --git a/src/Main/Base/Project/Src/Gui/WorkbenchSingleton.cs b/src/Main/Base/Project/Src/Gui/WorkbenchSingleton.cs
index 5946de4e13..63511676d0 100644
--- a/src/Main/Base/Project/Src/Gui/WorkbenchSingleton.cs
+++ b/src/Main/Base/Project/Src/Gui/WorkbenchSingleton.cs
@@ -19,7 +19,7 @@ namespace ICSharpCode.SharpDevelop.Gui
 		const string workbenchMemento        = "WorkbenchMemento";
 		
 		static STAThreadCaller caller;
-		static DefaultWorkbench workbench    = null;
+		static DefaultWorkbench workbench;
 		
 		public static Form MainForm {
 			get {
@@ -27,6 +27,9 @@ namespace ICSharpCode.SharpDevelop.Gui
 			}
 		}
 		
+		/// <summary>
+		/// Gets the workbench. Returns null in unit-testing mode.
+		/// </summary>
 		public static IWorkbench Workbench {
 			get {
 				return workbench;