diff --git a/entityreference.handler.inc b/entityreference.handler.inc
index e66b414..07f4a37 100644
--- a/entityreference.handler.inc
+++ b/entityreference.handler.inc
@@ -1,6 +1,12 @@
 <?php
 
 /**
+ * @file
+ * Interface and default implementation for the business logic of an
+ * entityreference field.
+ */
+
+/**
  * Abstraction of the business logic of an entity reference field.
  *
  * Implementations that wish to provide an implementation of this should
diff --git a/entityreference.install b/entityreference.install
index caae34e..e6aed25 100644
--- a/entityreference.install
+++ b/entityreference.install
@@ -1,6 +1,11 @@
 <?php
 
 /**
+ * @file
+ * Install file for the Entity Reference module.
+ */
+
+/**
  * Implements hook_field_schema().
  */
 function entityreference_field_schema($field) {
diff --git a/entityreference.module b/entityreference.module
index 60230a7..219ab6d 100644
--- a/entityreference.module
+++ b/entityreference.module
@@ -18,7 +18,7 @@ function entityreference_ctools_plugin_type() {
 }
 
 /**
- * Implementation of hook_field_info().
+ * Implements hook_field_info().
  */
 function entityreference_field_info() {
   $field_info['entityreference'] = array(
@@ -467,10 +467,18 @@ function entityreference_autocomplete_callback($type, $field_name, $entity_type,
   $field = field_info_field($field_name);
   $instance = field_info_instance($entity_type, $field_name, $bundle_name);
   $matches = array();
-
-  if (!$field || !$instance || $field['type'] != 'entityreference' || !field_access('edit', $field, $entity_type)) {
+  $widget_types = field_info_widget_types();
+  $field_type_is_allowed = FALSE;
+  foreach (array_keys(entityreference_field_widget_info()) as $widget_type) {
+    if (in_array($field['type'], $widget_types[$widget_type]['field types'])) {
+      $field_type_is_allowed = TRUE;
+      break;
+    }
+  }
+  if (!$field || !$instance || !$field_type_is_allowed || !field_access('edit', $field, $entity_type)) {
     return MENU_ACCESS_DENIED;
   }
+  unset($field_type_is_allowed, $widget_type, $widget_types);
 
   $handler = entityreference_get_handler($field);
 
diff --git a/handler/base.inc b/handler/base.inc
index 1a122df..f63ed18 100644
--- a/handler/base.inc
+++ b/handler/base.inc
@@ -1,5 +1,10 @@
 <?php
 
+/**
+ * @file
+ * Entity Reference handler plugin for core entities.
+ */
+
 $plugin = array(
   'title' => t('Simple (with optional filter by bundle)'),
   'handler' => 'EntityReferenceHandler_base',
@@ -110,7 +115,7 @@ class EntityReferenceHandler_base implements EntityReferenceHandler {
   protected function buildEntityFieldQuery($match = NULL, $match_operator = 'CONTAINS') {
     $query = new EntityFieldQuery();
     $query->entityCondition('entity_type', $this->field['settings']['target_type']);
-    if ($this->field['settings']['handler_settings']['target_bundles']) {
+    if (!empty($this->field['settings']['handler_settings']['target_bundles'])) {
       $query->entityCondition('bundle', $this->field['settings']['handler_settings']['target_bundles'], 'IN');
     }
     if (isset($match)) {
diff --git a/tests/entityreference.handlers.test b/tests/entityreference.handlers.test
index ae9266d..3599ca1 100644
--- a/tests/entityreference.handlers.test
+++ b/tests/entityreference.handlers.test
@@ -1,6 +1,11 @@
 <?php
 
 /**
+ * @file
+ * Test classes for Entity Reference
+ */
+
+/**
  * Test for Entity Reference handlers.
  */
 class EntityReferenceHandlersTestCase extends DrupalWebTestCase {