diff --git a/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlTreeViewControl.cs b/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlTreeViewControl.cs
index 671df936b3..f9d8a62a86 100644
--- a/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlTreeViewControl.cs
+++ b/src/AddIns/DisplayBindings/XmlEditor/Project/Src/XmlTreeViewControl.cs
@@ -123,7 +123,7 @@ namespace ICSharpCode.XmlEditor
 		/// </summary>
 		public void SaveViewState(Properties properties)
 		{
-			properties.Set(ViewStatePropertyName, ExtTreeView.GetViewStateString(this));
+			properties.Set(ViewStatePropertyName, TreeViewHelper.GetViewStateString(this));
 		}
 		
 		/// <summary>
@@ -131,7 +131,7 @@ namespace ICSharpCode.XmlEditor
 		/// </summary>
 		public void RestoreViewState(Properties properties)
 		{
-			ExtTreeView.ApplyViewStateString(properties.Get(ViewStatePropertyName, String.Empty), this);
+			TreeViewHelper.ApplyViewStateString(properties.Get(ViewStatePropertyName, String.Empty), this);
 		}
 		
 		/// <summary>
diff --git a/src/AddIns/DisplayBindings/XmlEditor/Test/Tree/TreeControlViewStateTestFixture.cs b/src/AddIns/DisplayBindings/XmlEditor/Test/Tree/TreeControlViewStateTestFixture.cs
index 5834e9f56e..055880f42e 100644
--- a/src/AddIns/DisplayBindings/XmlEditor/Test/Tree/TreeControlViewStateTestFixture.cs
+++ b/src/AddIns/DisplayBindings/XmlEditor/Test/Tree/TreeControlViewStateTestFixture.cs
@@ -32,7 +32,7 @@ namespace XmlEditor.Tests.Tree
 				treeView.Document = doc;
 				ExtTreeNode node = (ExtTreeNode)treeView.Nodes[0];
 				node.Expanding();
-				expectedSavedViewState = ExtTreeView.GetViewStateString(treeView);
+				expectedSavedViewState = TreeViewHelper.GetViewStateString(treeView);
 				treeView.SaveViewState(savedProperties);
 			}