diff --git a/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/Messages.java b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/Messages.java
new file mode 100644
index 0000000..1b729fe
--- /dev/null
+++ b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/Messages.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2011 Google Inc.
+ *
+ * All rights reserved. This program and the accompanying materials are made available under the terms of the Eclipse
+ * Public License v1.0 which accompanies this distribution, and is available at
+ *
+ * http://www.eclipse.org/legal/epl-v10.html
+ */
+package com.google.eclipse.protobuf.ui.outline;
+
+import org.eclipse.osgi.util.NLS;
+
+/**
+ * @author alruiz@google.com (Alex Ruiz)
+ */
+public class Messages extends NLS {
+  
+  public static String importDeclarations;
+  public static String optionDeclarations;
+  
+  static {
+    Class<Messages> targetType = Messages.class;
+    NLS.initializeMessages(targetType.getName(), targetType);
+  }
+
+  private Messages() {}
+}
diff --git a/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/Messages.properties b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/Messages.properties
new file mode 100644
index 0000000..fbd7d57
--- /dev/null
+++ b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/Messages.properties
@@ -0,0 +1,2 @@
+importDeclarations=import declarations
+optionDeclarations=option declarations
diff --git a/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/ProtobufOutlineTreeProvider.java b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/ProtobufOutlineTreeProvider.java
index 6d1ed58..2c63379 100644
--- a/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/ProtobufOutlineTreeProvider.java
+++ b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/outline/ProtobufOutlineTreeProvider.java
@@ -9,6 +9,10 @@
 package com.google.eclipse.protobuf.ui.outline;
 
 import static com.google.eclipse.protobuf.protobuf.ProtobufPackage.Literals.*;
+import static com.google.eclipse.protobuf.ui.outline.Messages.*;
+
+import java.util.ArrayList;
+import java.util.List;
 
 import org.eclipse.emf.ecore.EObject;
 import org.eclipse.xtext.ui.editor.outline.IOutlineNode;
@@ -25,6 +29,13 @@
  */
 public class ProtobufOutlineTreeProvider extends DefaultOutlineTreeProvider {
 
+  private static final List<Class<? extends EObject>> IGNORED_ELEMENT_TYPES = new ArrayList<Class<? extends EObject>>();
+  
+  static {
+    IGNORED_ELEMENT_TYPES.add(BooleanRef.class);
+    IGNORED_ELEMENT_TYPES.add(MessageReference.class);
+  }
+  
   boolean _isLeaf(Option o) {
     return true;
   }
@@ -40,11 +51,11 @@
     }
     if (!protobuf.getImports().isEmpty()) {
       createEStructuralFeatureNode(parentNode, protobuf, PROTOBUF__IMPORTS,
-          labelProvider.getImage("imports"), "import declarations", false);
+          labelProvider.getImage("imports"), importDeclarations, false);
     }
     if (!protobuf.getOptions().isEmpty()) {
       createEStructuralFeatureNode(parentNode, protobuf, PROTOBUF__OPTIONS,
-          labelProvider.getImage("options"), "option declarations", false);
+          labelProvider.getImage("options"), optionDeclarations, false);
     }
     for (ProtobufElement e : protobuf.getElements()) {
       createNode(parentNode, e);
@@ -52,7 +63,13 @@
   }
 
   @Override protected void createNode(IOutlineNode parent, EObject modelElement) {
-    if (modelElement instanceof MessageReference) return;
+    if (isIgnored(modelElement)) return;
     super.createNode(parent, modelElement);
   }
+  
+  private boolean isIgnored(EObject modelElement) {
+    for (Class<? extends EObject> ignoredType : IGNORED_ELEMENT_TYPES)
+      if (ignoredType.isInstance(modelElement)) return true;
+    return false;
+  }
 }
diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext
index 5a320c3..d72264c 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/Protobuf.xtext
@@ -50,7 +50,7 @@
   Type | Property | Group | ExtendMessage;
 
 Group:
-  modifier=Modifier 'group' name=ID '=' index=INT '{'
+  modifier=Modifier 'group' name=ID '=' index=INT ('[' 'deprecated' '=' deprecated=BooleanRef ']')? '{'
   elements+=Property*
   '}'(';')?;