diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 2664a42..c4fa6b5 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -207,6 +207,13 @@ const LANGUAGE_NOT_APPLICABLE = 'zxx';
 const LANGUAGE_MULTIPLE = 'mul';
 
 /**
+ * The language code used when referring to all languages.
+ *
+ * @todo W3C uses this for 'Allar', need to find a better code.
+ */
+const LANGUAGE_ALL = 'all';
+
+/**
  * The type of language used to define the content language.
  */
 const LANGUAGE_TYPE_CONTENT = 'language_content';
@@ -2540,6 +2547,84 @@ function language_list($only_enabled = FALSE) {
 }
 
 /**
+ * Prepare a list of languages for use on the interface.
+ *
+ * @param $options
+ *   (optional) An array of options to limit/extend the standard langugae list
+ *   based on where is the list going to be used.
+ *   - 'english': set to FALSE to remove the English language.
+ *   - 'system': set to TRUE to add the special LANGUAGE_SYSTEM language.
+ *   - 'content': set to TRUE to add the LANGUAGE_NOT_SPECIFIED,
+ *   LANGUAGE_NOT_APPLICABLE and LANGUAGE_MULTIPLE special languages.
+ *
+ * @return
+ *   An associative array of languages, keyed by the language code, ordered by
+ *   weight ascending and name ascending.
+ */
+function language_list_prepare($languages, $options = array()) {
+  $options += array(
+    'english' => TRUE,
+  );
+
+  // Language list is ordered by weight, get the biggest one.
+  $keys = array_keys($languages);
+  $max_weight = $languages[array_pop($keys)]->weight;
+
+  if (empty($options['english'])) {
+    unset($languages['en']);
+  }
+
+  $locked_language = array(
+    'default' => FALSE,
+    'locked' => TRUE,
+    'enabled' => TRUE,
+  );
+
+  if (!empty($options['system'])) {
+    $languages[LANGUAGE_SYSTEM] = (object) (array(
+      'langcode' => LANGUAGE_SYSTEM,
+      'name' => t('System (English)'),
+      'weight' => ++$max_weight,
+      'description' => t('Built-in language for interface translation.'),
+    ) + $locked_language);
+  }
+
+  if (!empty($options['content'])) {
+    $languages[LANGUAGE_NOT_SPECIFIED] = (object) (array(
+      'langcode' => LANGUAGE_NOT_SPECIFIED,
+      'name' => t('Not specified'),
+      'weight' => ++$max_weight,
+      'description' => t('May be assigned to content.'),
+    ) + $locked_language);
+    $languages[LANGUAGE_NOT_APPLICABLE] = (object) (array(
+      'langcode' => LANGUAGE_NOT_APPLICABLE,
+      'name' => t('Not applicable'),
+      'weight' => ++$max_weight,
+      'description' => t('May be assigned to content.'),
+    ) + $locked_language);
+    $languages[LANGUAGE_MULTIPLE] = (object) (array(
+      'langcode' => LANGUAGE_MULTIPLE,
+      'name' => t('Multiple'),
+      'weight' => ++$max_weight,
+      'description' => t('May be assigned to content.'),
+    ) + $locked_language);
+  }
+
+  if (!empty($options['all'])) {
+    $languages[LANGUAGE_ALL] = (object) (array(
+      'langcode' => LANGUAGE_ALL,
+      'name' => t('All languages'),
+      'weight' => ++$max_weight,
+    ) + $locked_language);
+  }
+
+  // Let other modules alter the list.
+  drupal_alter('language_list_prepare', $languages, $options);
+
+  return $languages;
+}
+
+/**
  * Loads a language object from the database.
  *
  * @param $langcode
@@ -2563,14 +2648,21 @@ function language_load($langcode) {
  *   The printed name of the language.
  */
 function language_name($langcode) {
+  if (empty($langcode)) {
+    return t('Unknown');
+  }
   if ($langcode == LANGUAGE_NOT_SPECIFIED) {
-    return t('None');
+    return t('Not specified');
+  }
+  if ($langcode == LANGUAGE_NOT_APPLICABLE) {
+    return t('Not applicable');
+  }
+  if ($langcode == LANGUAGE_MULTIPLE) {
+    return t('Multiple');
   }
-
   if ($language = language_load($langcode)) {
     return $language->name;
   }
-
   return t('Unknown (@langcode)', array('@langcode' => $langcode));
 }
 
diff --git a/core/modules/language/language.admin.inc b/core/modules/language/language.admin.inc
index 33bc147..abddc6f 100644
--- a/core/modules/language/language.admin.inc
+++ b/core/modules/language/language.admin.inc
@@ -10,7 +10,7 @@
  */
 function language_admin_overview_form($form, &$form_state) {
   drupal_static_reset('language_list');
-  $languages = language_list();
+  $languages = language_list_prepare(language_list(), array('content' => TRUE, 'system' => TRUE));
   $default = language_default();
 
   $form['languages'] = array(
@@ -29,8 +29,12 @@ function language_admin_overview_form($form, &$form_state) {
 
   foreach ($languages as $langcode => $language) {
     $form['languages'][$langcode]['#weight'] = $language->weight;
+    $title = check_plain($language->name);
+    if (!empty($language->description)) {
+      $title .= '<div class="description">' . $language->description . '</div>';
+    }
     $form['languages'][$langcode]['name'] = array(
-      '#markup' => check_plain($language->name),
+      '#markup' => $title,
     );
     $form['languages'][$langcode]['enabled'] = array(
       '#type' => 'checkbox',
@@ -53,25 +57,32 @@ function language_admin_overview_form($form, &$form_state) {
       '#title' => t('Weight for @title', array('@title' => $language->name)),
       '#title_display' => 'invisible',
       '#default_value' => $language->weight,
-      '#attributes' => array(
-        'class' => array('language-order-weight'),
-      ),
     );
     $form['languages'][$langcode]['operations'] = array(
       '#theme_wrappers' => array('language_admin_operations'),
       '#weight' => 100,
     );
-    $form['languages'][$langcode]['operations']['edit'] = array(
-      '#type' => 'link',
-      '#title' => t('edit'),
-      '#href' => 'admin/config/regional/language/edit/' . $langcode,
-    );
-    $form['languages'][$langcode]['operations']['delete'] = array(
-      '#type' => 'link',
-      '#title' => t('delete'),
-      '#href' => 'admin/config/regional/language/delete/' . $langcode,
-      '#access' => $langcode != $default->langcode,
-    );
+    if (empty($language->locked)) {
+      $form['languages'][$langcode]['weight']['#attributes'] = array(
+        'class' => array('language-order-weight'),
+      );
+      $form['languages'][$langcode]['operations']['edit'] = array(
+        '#type' => 'link',
+        '#title' => t('edit'),
+        '#href' => 'admin/config/regional/language/edit/' . $langcode,
+      );
+      $form['languages'][$langcode]['operations']['delete'] = array(
+        '#type' => 'link',
+        '#title' => t('delete'),
+        '#href' => 'admin/config/regional/language/delete/' . $langcode,
+        '#access' => $langcode != $default->langcode,
+      );
+    }
+    else {
+      $form['languages'][$langcode]['default']['#disabled'] = TRUE;
+      $form['languages'][$langcode]['enabled']['#disabled'] = TRUE;
+      $form['languages'][$langcode]['weight']['#type'] = 'value';
+    }
   }
 
   $form['actions'] = array('#type' => 'actions');
@@ -122,9 +133,10 @@ function theme_language_admin_overview_form_table($variables) {
   $rows = array();
   foreach (element_children($form, TRUE) as $langcode) {
     $element = &$form[$langcode];
-    $row = array(
-      'class' => array('draggable'),
-    );
+    $row = array();
+    if (empty($form['#languages'][$langcode]->locked)) {
+      $row['class'] = array('draggable');
+    }
     foreach (element_children($element, TRUE) as $column) {
       $cell = &$element[$column];
       $row['data'][] = drupal_render($cell);
diff --git a/core/modules/locale/locale.module b/core/modules/locale/locale.module
index c49dabe..41cd367 100644
--- a/core/modules/locale/locale.module
+++ b/core/modules/locale/locale.module
@@ -1018,7 +1018,7 @@ function locale_form_language_admin_overview_form_alter(&$form, &$form_state) {
       'translated' => 0,
       'ratio' => 0,
     );
-    if ($langcode != 'en' || locale_translate_english()) {
+    if (empty($language->locked) && ($langcode != 'en' || locale_translate_english())) {
       $form['languages'][$langcode]['locale_statistics'] = array(
         '#type' => 'link',
         '#title' => t('@translated/@total (@ratio%)', array(
@@ -1029,9 +1029,14 @@ function locale_form_language_admin_overview_form_alter(&$form, &$form_state) {
         '#href' => 'admin/config/regional/translate/translate',
       );
     }
+    elseif ($langcode == LANGUAGE_SYSTEM) {
+      $form['languages'][$langcode]['locale_statistics'] = array(
+        '#markup' => t('Built-in'),
+      );
+    }
     else {
       $form['languages'][$langcode]['locale_statistics'] = array(
-        '#markup' => t('not applicable'),
+        '#markup' => t('Not applicable'),
       );
     }
   }
diff --git a/core/modules/locale/locale.pages.inc b/core/modules/locale/locale.pages.inc
index e41bae5..af71111 100644
--- a/core/modules/locale/locale.pages.inc
+++ b/core/modules/locale/locale.pages.inc
@@ -28,7 +28,7 @@ function _locale_translate_seek() {
   if (!($query = _locale_translate_seek_query())) {
     $query = array(
       'translation' => 'all',
-      'language' => 'all',
+      'language' => LANGUAGE_ALL,
       'string' => '',
     );
   }
@@ -64,7 +64,7 @@ function _locale_translate_seek() {
   }
 
   $limit_language = NULL;
-  if ($query['language'] != LANGUAGE_SYSTEM && $query['language'] != 'all') {
+  if ($query['language'] != LANGUAGE_SYSTEM && $query['language'] != LANGUAGE_ALL) {
     $sql_query->condition('language', $query['language']);
     $limit_language = $query['language'];
   }
@@ -152,12 +152,10 @@ function locale_translation_filters() {
 
   // Get all languages, except English
   drupal_static_reset('language_list');
-  $languages = language_list(TRUE);
+  $languages = language_list_prepare(language_list(TRUE), array('system' => TRUE, 'english' => locale_translate_english(), 'all' => TRUE));
   $language_options = array();
   foreach ($languages as $langcode => $language) {
-    if ($langcode != 'en' || locale_translate_english()) {
-      $language_options[$langcode] = $language->name;
-    }
+    $language_options[$langcode] = $language->name;
   }
 
   $filters['string'] = array(
@@ -167,7 +165,7 @@ function locale_translation_filters() {
 
   $filters['language'] = array(
     'title' => t('Language'),
-    'options' => array_merge(array('all' => t('All languages'), LANGUAGE_SYSTEM => t('System (English)')), $language_options),
+    'options' => $language_options,
   );
 
   $filters['translation'] = array(
diff --git a/core/modules/node/node.pages.inc b/core/modules/node/node.pages.inc
index 4e94b26..c0fd658 100644
--- a/core/modules/node/node.pages.inc
+++ b/core/modules/node/node.pages.inc
@@ -176,7 +176,7 @@ function node_form($form, &$form_state, $node) {
   $form['#node'] = $node;
 
   if (variable_get('node_type_language_' . $node->type, 0) && module_exists('language')) {
-    $languages = language_list(TRUE);
+    $languages = language_list_prepare(language_list(TRUE), array('content' => TRUE));
     $language_options = array();
     foreach ($languages as $langcode => $language) {
       $language_options[$langcode] = $language->name;
@@ -184,9 +184,8 @@ function node_form($form, &$form_state, $node) {
     $form['langcode'] = array(
       '#type' => 'select',
       '#title' => t('Language'),
-      '#default_value' => (isset($node->langcode) ? $node->langcode : ''),
+      '#default_value' => (isset($node->langcode) ? $node->langcode : LANGUAGE_NOT_SPECIFIED),
       '#options' => $language_options,
-      '#empty_value' => LANGUAGE_NOT_SPECIFIED,
     );
   }
   else {