diff --git a/modules/field/modules/list/list.module b/modules/field/modules/list/list.module
index b569f8c8ea039b07ac3c0d52778bd15789f00cea..64d8441ca0ac2f92d9168f0ad8fb08b252394dc4 100644
--- a/modules/field/modules/list/list.module
+++ b/modules/field/modules/list/list.module
@@ -224,20 +224,31 @@ function list_allowed_values_list($string_values, $position_keys = FALSE) {
 function list_allowed_values_validate($element, &$form_state) {
   $values = list_allowed_values_list($element['#value'], $element['#list_field_type'] == 'list');
   $field_type = $element['#list_field_type'];
+
+  // Check that keys are valid for the field type.
   foreach ($values as $key => $value) {
     if ($field_type == 'list_number' && !is_numeric($key)) {
-      form_error($element, t('The entered available values are not valid. Each key must be a valid integer or decimal.'));
+      form_error($element, t('Allowed values list: each key must be a valid integer or decimal.'));
       break;
     }
     elseif ($field_type == 'list_text' && strlen($key) > 255) {
-      form_error($element, t('The entered available values are not valid. Each key must be a string less than 255 characters.'));
+      form_error($element, t('Allowed values list: each key must be a string less than 255 characters.'));
+      break;
+    }
+    elseif ($field_type == 'list' && !preg_match('/^-?\d+$/', $key)) {
+      form_error($element, t('Allowed values list: keys must be integers.'));
       break;
     }
-    elseif ($field_type == 'list' && (!preg_match('/^-?\d+$/', $key))) {
-      form_error($element, t('The entered available values are not valid. All specified keys must be integers.'));
+    elseif ($field_type == 'list_boolean' && !in_array($key, array('0', '1'))) {
+      form_error($element, t('Allowed values list: keys must be either 0 or 1.'));
       break;
     }
   }
+
+  // Check that boolean fields get two values.
+  if ($field_type == 'list_boolean' && count($values) != 2) {
+    form_error($element, t('Allowed values list: two values are required.'));
+  }
 }
 
 /**
diff --git a/modules/field/modules/list/list.test b/modules/field/modules/list/list.test
index 7f8a1dc62cade2fce69fc744a87a8ec98d3ab278..de9c29e41ebb576538f7ce220d3e446b5da57a9e 100644
--- a/modules/field/modules/list/list.test
+++ b/modules/field/modules/list/list.test
@@ -85,5 +85,89 @@ class ListFieldTestCase extends DrupalWebTestCase {
     $this->assertTrue(!empty($form['card_1'][FIELD_LANGUAGE_NONE][2]), t('Option 2 exists'));
     $this->assertTrue(!empty($form['card_1'][FIELD_LANGUAGE_NONE][3]), t('Option 3 exists'));
   }
+  
+}
+
+/**
+* List module UI tests.
+*/
+class ListFieldUITestCase extends DrupalWebTestCase {
+    public static function getInfo() {
+    return array(
+      'name' => 'List field UI tests',
+      'description' => 'Test the List field UI functionality.',
+      'group' => 'Field types',
+    );
+  }
+  
+  function setUp() {
+    FieldUITestCase::setUp();
+  }
+   
+  /**
+   * Tests that allowed values are properly validated in the UI.
+   */
+  function testAllowedValues() {
+    $element_name = "field[settings][allowed_values]";
+    
+    //Test 'List' field type.
+    $admin_path = $this->createListFieldAndEdit('list');
+    //Check that non-integer keys are rejected.
+    $edit = array($element_name => "1.1|one\n");
+    $this->drupalPost($admin_path, $edit, t('Save settings'));
+    $this->assertText("keys must be integers", t('Form vaildation failed.'));
+    
+    // Test 'List (number)' field type.
+    $admin_path = $this->createListFieldAndEdit('list_number');
+    //Check that non-numeric keys are rejected.
+    $edit = array($element_name => "1|one\nB|two");
+    $this->drupalPost($admin_path, $edit, t('Save settings'));
+    $this->assertText("each key must be a valid integer or decimal", t('Form vaildation failed.'));
+
+    //Test 'List (text)' field type.
+    $admin_path = $this->createListFieldAndEdit('list_text');
+    //Check that over long keys are rejected.
+    $edit = array($element_name => "1|one\n" . $this->randomName(255) . "|two");
+    $this->drupalPost($admin_path, $edit, t('Save settings'));
+    $this->assertText("each key must be a string less than 255 characters", t('Form vaildation failed.'));
+    
+    // Test 'List (boolean)' field type.
+    $admin_path = $this->createListFieldAndEdit('list_boolean');    
+    // Check that invalid option keys are rejected.
+    $edit = array($element_name => "1|one\n2|two");
+    $this->drupalPost($admin_path, $edit, t('Save settings'));
+    $this->assertText("keys must be either 0 or 1", t('Form vaildation failed.'));
+    
+    //Check that missing option causes failure.
+    $edit = array($element_name => "1|one");
+    $this->drupalPost($admin_path, $edit, t('Save settings'));
+    $this->assertText("two values are required", t('Form vaildation failed.'));    
+  }
+  
+  /**
+   * Helper function to create list field of a given type and get the edit page.
+   * 
+   * @param string $type
+   *   'list', 'list_boolean', 'list_number', or 'list_text'
+   */
+  private function createListFieldAndEdit($type) {
+    // Create a test field and instance.
+    $field_name = 'test_' . $type;
+    $field = array(
+      'field_name' => $field_name,
+      'type' => $type,
+    );
+    field_create_field($field);
+    $instance = array(
+      'field_name' => $field_name,
+      'object_type' => 'node',
+      'bundle' => $this->type,
+    );
+    field_create_instance($instance);
+
+    $admin_path = 'admin/structure/types/manage/' . $this->hyphen_type . '/fields/' . $field_name;
+    return $admin_path;
+  }
+  
 }