diff --git a/src/Main/Base/Project/Src/Services/RefactoringService/FindReferencesAndRenameHelper.cs b/src/Main/Base/Project/Src/Services/RefactoringService/FindReferencesAndRenameHelper.cs
index 2dc6e5b5c7..4235d30ed7 100644
--- a/src/Main/Base/Project/Src/Services/RefactoringService/FindReferencesAndRenameHelper.cs
+++ b/src/Main/Base/Project/Src/Services/RefactoringService/FindReferencesAndRenameHelper.cs
@@ -54,7 +54,7 @@ namespace ICSharpCode.SharpDevelop.Refactoring
 				                                                     1,
 				                                                     "${res:Global.ReplaceButtonText}",
 				                                                     "${res:Global.AbortButtonText}");
-				if (confirmReplace == 1) {
+				if (confirmReplace != 0) {
 					return;
 				}
 			}
diff --git a/src/Main/Core/Project/Src/Services/MessageService/IMessageService.cs b/src/Main/Core/Project/Src/Services/MessageService/IMessageService.cs
index bd9fd54973..711362f8ac 100644
--- a/src/Main/Core/Project/Src/Services/MessageService/IMessageService.cs
+++ b/src/Main/Core/Project/Src/Services/MessageService/IMessageService.cs
@@ -48,7 +48,7 @@ namespace ICSharpCode.Core.Services
 		/// Use -1 if you don't want to have a cancel button.
 		/// </param>
 		/// <param name="buttontexts">The captions of the buttons.</param>
-		/// <returns>The number of the button that was clicked.</returns>
+		/// <returns>The number of the button that was clicked, or -1 if the dialog was closed  without clicking a button.</returns>
 		int ShowCustomDialog(string caption, string dialogText, int acceptButtonIndex, int cancelButtonIndex, params string[] buttontexts);
 		string ShowInputBox(string caption, string dialogText, string defaultValue);
 		void ShowMessage(string message, string caption);
diff --git a/src/Main/Core/Project/Src/Services/MessageService/MessageService.cs b/src/Main/Core/Project/Src/Services/MessageService/MessageService.cs
index 0c07648b72..083b166266 100644
--- a/src/Main/Core/Project/Src/Services/MessageService/MessageService.cs
+++ b/src/Main/Core/Project/Src/Services/MessageService/MessageService.cs
@@ -142,7 +142,7 @@ namespace ICSharpCode.Core
 		/// Use -1 if you don't want to have a cancel button.
 		/// </param>
 		/// <param name="buttontexts">The captions of the buttons.</param>
-		/// <returns>The number of the button that was clicked.</returns>
+		/// <returns>The number of the button that was clicked, or -1 if the dialog was closed  without clicking a button.</returns>
 		public static int ShowCustomDialog(string caption, string dialogText, int acceptButtonIndex, int cancelButtonIndex, params string[] buttontexts)
 		{
 			return ServiceManager.MessageService.ShowCustomDialog(caption, dialogText, acceptButtonIndex, cancelButtonIndex, buttontexts);
diff --git a/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/Refactoring/NRefactoryRefactoringProvider.cs b/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/Refactoring/NRefactoryRefactoringProvider.cs
index a8b42bc000..97ab793c07 100644
--- a/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/Refactoring/NRefactoryRefactoringProvider.cs
+++ b/src/Main/ICSharpCode.SharpDevelop.Dom/Project/Src/Refactoring/NRefactoryRefactoringProvider.cs
@@ -96,6 +96,10 @@ namespace ICSharpCode.SharpDevelop.Dom.Refactoring
 		public override string GenerateInterfaceForClass(string newInterfaceName, string existingCode, IList<IMember> membersToKeep, IClass sourceClass, bool preserveComments)
 		{
 			Modifiers modifiers = CodeGenerator.ConvertModifier(sourceClass.Modifiers, new ClassFinder(membersToKeep[0]));
+			// keep only visibility modifiers and 'unsafe' modifier
+			// -> remove abstract,sealed,static
+			modifiers &= Modifiers.Visibility | Modifiers.Unsafe;
+			
 			TypeDeclaration interfaceDef = new TypeDeclaration(modifiers, new List<AttributeSection>());
 			interfaceDef.Name = newInterfaceName;
 			interfaceDef.Type = NR.Ast.ClassType.Interface;