diff --git a/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue147_AddSupportForGroupOptions_Test.java b/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue147_AddSupportForGroupOptions_Test.java
index c394448..be37f9d 100644
--- a/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue147_AddSupportForGroupOptions_Test.java
+++ b/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue147_AddSupportForGroupOptions_Test.java
@@ -28,21 +28,21 @@
 
 /**
  * Tests fix for <a href="http://code.google.com/p/protobuf-dt/issues/detail?id=147">Issue 147</a>.
- * 
+ *
  * @author alruiz@google.com (Alex Ruiz)
  */
 public class Issue147_AddSupportForGroupOptions_Test {
 
   private static EReference reference;
-  
+
   @BeforeClass public static void setUpOnce() {
     reference = mock(EReference.class);
   }
-  
+
   @Rule public XtextRule xtext = createWith(integrationTestSetup());
-  
+
   private ProtobufScopeProvider provider;
-  
+
   @Before public void setUp() {
     provider = xtext.getInstanceOf(ProtobufScopeProvider.class);
   }
@@ -52,37 +52,37 @@
   //     required int64 groupId = 2;
   //   }
   // }
-  @Test public void should_provide_Property_fields_for_native_option() {
+  @Test public void should_provide_fields_for_native_option() {
     NativeFieldOption option = xtext.find("deprecated", NativeFieldOption.class);
     IScope scope = provider.scope_OptionSource_optionField(option.getSource(), reference);
     Collection<Property> fieldOptions = descriptor().optionsOfType(FIELD);
     assertThat(descriptionsIn(scope), containAll(fieldOptions));
   }
-  
+
   private ProtoDescriptor descriptor() {
     ProtoDescriptorProvider descriptorProvider = xtext.getInstanceOf(ProtoDescriptorProvider.class);
     return descriptorProvider.primaryDescriptor();
   }
-  
+
   // package com.google.proto;
   // import 'google/protobuf/descriptor.proto';
-  //  
+  //
   // extend google.protobuf.FieldOptions {
   //   optional int32 code = 1000;
   //   optional int32 info = 1001;
   // }
-  //  
+  //
   // message Person {
   //   repeated group membership = 1 [(code) = 68] {
   //     required int64 groupId = 2;
   //   }
   // }
-  @Test public void should_provide_Property_fields_for_custom_option() {
+  @Test public void should_provide_fields_for_custom_option() {
     CustomFieldOption option = xtext.find("code", ")", CustomFieldOption.class);
     IScope scope = provider.scope_OptionSource_optionField(option.getSource(), reference);
-    assertThat(descriptionsIn(scope), containAll("code", "proto.code", "google.proto.code", "com.google.proto.code", 
+    assertThat(descriptionsIn(scope), containAll("code", "proto.code", "google.proto.code", "com.google.proto.code",
                                                  ".com.google.proto.code",
-                                                 "info", "proto.info", "google.proto.info", "com.google.proto.info", 
+                                                 "info", "proto.info", "google.proto.info", "com.google.proto.info",
                                                  ".com.google.proto.info"));
   }
 }
diff --git a/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue156_AddSupportForEnumValueOptions_Test.java b/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue156_AddSupportForEnumValueOptions_Test.java
new file mode 100644
index 0000000..df88541
--- /dev/null
+++ b/com.google.eclipse.protobuf.integration.test/src/com/google/eclipse/protobuf/scoping/Issue156_AddSupportForEnumValueOptions_Test.java
@@ -0,0 +1,60 @@
+/*
+ * 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.scoping;
+
+import static com.google.eclipse.protobuf.junit.core.Setups.integrationTestSetup;
+import static com.google.eclipse.protobuf.junit.core.XtextRule.createWith;
+import static com.google.eclipse.protobuf.scoping.ContainAllNames.containAll;
+import static com.google.eclipse.protobuf.scoping.IEObjectDescriptions.descriptionsIn;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.mock;
+
+import org.eclipse.emf.ecore.EReference;
+import org.eclipse.xtext.scoping.IScope;
+import org.junit.*;
+
+import com.google.eclipse.protobuf.junit.core.XtextRule;
+import com.google.eclipse.protobuf.protobuf.CustomFieldOption;
+
+/**
+ * Tests fix for <a href="http://code.google.com/p/protobuf-dt/issues/detail?id=156">Issue 156</a>.
+ *
+ * @author alruiz@google.com (Alex Ruiz)
+ */
+public class Issue156_AddSupportForEnumValueOptions_Test {
+
+  private static EReference reference;
+
+  @BeforeClass public static void setUpOnce() {
+    reference = mock(EReference.class);
+  }
+
+  @Rule public XtextRule xtext = createWith(integrationTestSetup());
+
+  private ProtobufScopeProvider provider;
+
+  @Before public void setUp() {
+    provider = xtext.getInstanceOf(ProtobufScopeProvider.class);
+  }
+
+  // import 'google/protobuf/descriptor.proto';
+  //
+  // extend google.protobuf.EnumValueOptions {
+  //   optional bool active = 1000;
+  // }
+  //
+  // enum PhoneType {
+  //   HOME = 0 [(active) = true];
+  // }
+  @Test public void should_provide_fields_for_custom_field_option() {
+    CustomFieldOption option = xtext.find("active", ")", CustomFieldOption.class);
+    IScope scope = provider.scope_OptionSource_optionField(option.getSource(), reference);
+    assertThat(descriptionsIn(scope), containAll("active", ".active"));
+  }
+}
diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java
index b4ea6f4..0c5a6cd 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java
@@ -11,8 +11,6 @@
 import java.util.*;
 import java.util.Map.Entry;
 
-import org.eclipse.emf.ecore.EObject;
-
 import com.google.eclipse.protobuf.protobuf.*;
 import com.google.eclipse.protobuf.protobuf.Enum;
 
@@ -31,6 +29,7 @@
   static {
     OPTION_TYPES_BY_CONTAINER.put(Protobuf.class, FILE);
     OPTION_TYPES_BY_CONTAINER.put(Enum.class, ENUM);
+    OPTION_TYPES_BY_CONTAINER.put(Literal.class, LITERAL);
     OPTION_TYPES_BY_CONTAINER.put(Message.class, MESSAGE);
     OPTION_TYPES_BY_CONTAINER.put(Field.class, FIELD);
     OPTION_TYPES_BY_CONTAINER.put(Service.class, SERVICE);
@@ -70,7 +69,7 @@
     return findOptionTypeForLevelOf(option.eContainer());
   }
 
-  static OptionType findOptionTypeForLevelOf(EObject container) {
+  static OptionType findOptionTypeForLevelOf(Object container) {
     for (Entry<Class<?>, OptionType> optionTypeByContainer : OPTION_TYPES_BY_CONTAINER.entrySet()) {
       if (optionTypeByContainer.getKey().isInstance(container)) {
         return optionTypeByContainer.getValue();