diff --git includes/form.inc includes/form.inc
index 1388351..0fbd55e 100644
--- includes/form.inc
+++ includes/form.inc
@@ -1350,7 +1350,7 @@ function form_type_textfield_value($form, $edit = FALSE) {
   if ($edit !== FALSE) {
     // Equate $edit to the form value to ensure it's marked for
     // validation.
-    return str_replace(array("\r", "\n"), '', $edit);
+    return trim(str_replace(array("\r", "\n"), '', $edit));
   }
 }
 
diff --git modules/comment/comment.module modules/comment/comment.module
index 3bc28c0..1d39502 100644
--- modules/comment/comment.module
+++ modules/comment/comment.module
@@ -1780,13 +1780,13 @@ function _comment_form_submit(&$comment_values) {
   }
 
   // Validate the comment's subject. If not specified, extract from comment body.
-  if (trim($comment_values['subject']) == '') {
+  if ($comment_values['subject'] == '') {
     // The body may be in any format, so:
     // 1) Filter it into HTML
     // 2) Strip out all HTML tags
     // 3) Convert entities back to plain-text.
     // Note: format is checked by check_markup().
-    $comment_values['subject'] = truncate_utf8(trim(decode_entities(strip_tags(check_markup($comment_values['comment'], $comment_values['comment_format'])))), 29, TRUE);
+    $comment_values['subject'] = truncate_utf8(decode_entities(strip_tags(check_markup($comment_values['comment'], $comment_values['comment_format']))), 29, TRUE);
     // Edge cases where the comment body is populated only by HTML tags will
     // require a default subject.
     if ($comment_values['subject'] == '') {
diff --git modules/filter/filter.admin.inc modules/filter/filter.admin.inc
index 3e0fc0b..41668d9 100644
--- modules/filter/filter.admin.inc
+++ modules/filter/filter.admin.inc
@@ -183,7 +183,7 @@ function filter_admin_format_form(&$form_state, $format) {
  */
 function filter_admin_format_form_validate($form, &$form_state) {
   if (!isset($form_state['values']['format'])) {
-    $name = trim($form_state['values']['name']);
+    $name = $form_state['values']['name'];
     $result = db_query("SELECT format FROM {filter_format} WHERE name = :name", array(':name' => $name))->fetchField();
     if ($result) {
       form_set_error('name', t('Text format names must be unique. A format named %name already exists.', array('%name' => $name)));
@@ -197,7 +197,7 @@ function filter_admin_format_form_validate($form, &$form_state) {
 function filter_admin_format_form_submit($form, &$form_state) {
   $format = isset($form_state['values']['format']) ? $form_state['values']['format'] : NULL;
   $current = filter_list_format($format);
-  $name = trim($form_state['values']['name']);
+  $name = $form_state['values']['name'];
   $cache = TRUE;
 
   // Add a new text format.
diff --git modules/menu/menu.admin.inc modules/menu/menu.admin.inc
index b452e04..0b190b2 100644
--- modules/menu/menu.admin.inc
+++ modules/menu/menu.admin.inc
@@ -365,7 +365,7 @@ function menu_edit_item_validate($form, &$form_state) {
       $item['link_path'] = $parsed_link['path'];
     }
   }
-  if (!trim($item['link_path']) || !menu_valid_path($item)) {
+  if (!$item['link_path'] || !menu_valid_path($item)) {
     form_set_error('link_path', t("The path '@link_path' is either invalid or you do not have access to it.", array('@link_path' => $item['link_path'])));
   }
 }
diff --git modules/menu/menu.module modules/menu/menu.module
index 70bb609..732d8ba 100644
--- modules/menu/menu.module
+++ modules/menu/menu.module
@@ -301,11 +301,10 @@ function menu_node_insert($node) {
     if (!empty($item['delete'])) {
       menu_link_delete($item['mlid']);
     }
-    elseif (trim($item['link_title'])) {
-      $item['link_title'] = trim($item['link_title']);
+    elseif ($item['link_title']) {
       $item['link_path'] = "node/$node->nid";
       if (!$item['customized']) {
-        $item['options']['attributes']['title'] = trim($node->title);
+        $item['options']['attributes']['title'] = $node->title;
       }
       if (!menu_link_save($item)) {
         drupal_set_message(t('There was an error saving the menu link.'), 'error');
@@ -323,11 +322,10 @@ function menu_node_update($node) {
     if (!empty($item['delete'])) {
       menu_link_delete($item['mlid']);
     }
-    elseif (trim($item['link_title'])) {
-      $item['link_title'] = trim($item['link_title']);
+    elseif ($item['link_title']) {
       $item['link_path'] = "node/$node->nid";
       if (!$item['customized']) {
-        $item['options']['attributes']['title'] = trim($node->title);
+        $item['options']['attributes']['title'] = $node->title;
       }
       if (!menu_link_save($item)) {
         drupal_set_message(t('There was an error saving the menu link.'), 'error');
diff --git modules/node/content_types.inc modules/node/content_types.inc
index e967193..81a9a00 100644
--- modules/node/content_types.inc
+++ modules/node/content_types.inc
@@ -252,11 +252,11 @@ function _node_characters($length) {
  */
 function node_type_form_validate($form, &$form_state) {
   $type = new stdClass();
-  $type->type = trim($form_state['values']['type']);
-  $type->name = trim($form_state['values']['name']);
+  $type->type = $form_state['values']['type'];
+  $type->name = $form_state['values']['name'];
 
   // Work out what the type was before the user submitted this form
-  $old_type = trim($form_state['values']['old_type']);
+  $old_type = $form_state['values']['old_type'];
 
   $types = node_type_get_names();
 
@@ -289,9 +289,9 @@ function node_type_form_submit($form, &$form_state) {
 
   $type = node_type_set_defaults();
 
-  $type->type = trim($form_state['values']['type']);
-  $type->name = trim($form_state['values']['name']);
-  $type->orig_type = trim($form_state['values']['orig_type']);
+  $type->type = $form_state['values']['type'];
+  $type->name = $form_state['values']['name'];
+  $type->orig_type = $form_state['values']['orig_type'];
   $type->old_type = isset($form_state['values']['old_type']) ? $form_state['values']['old_type'] : $type->type;
 
   $type->description = $form_state['values']['description'];
diff --git modules/node/node.module modules/node/node.module
index 31d32ba..a7894bf 100644
--- modules/node/node.module
+++ modules/node/node.module
@@ -2392,7 +2392,7 @@ function node_search_validate($form, &$form_state) {
     $keys .= ' "' . str_replace('"', ' ', $form_state['values']['phrase']) . '"';
   }
   if (!empty($keys)) {
-    form_set_value($form['basic']['inline']['processed_keys'], trim($keys), $form_state);
+    form_set_value($form['basic']['inline']['processed_keys'], $keys, $form_state);
   }
 }
 
diff --git modules/simpletest/tests/form.test modules/simpletest/tests/form.test
index a0973d7..389da15 100644
--- modules/simpletest/tests/form.test
+++ modules/simpletest/tests/form.test
@@ -346,6 +346,48 @@ class FormsFormCleanIdFunctionalTest extends DrupalWebTestCase {
 }
 
 /**
+ * Tests for form elements and their behaviors.
+ */
+class FormElementTest extends DrupalWebTestCase {
+
+  public static function getInfo() {
+    return array(
+      'name' => t('Form elements test'),
+      'description' => t('Tests for form elements and their behaviors'),
+      'group' => t('Form API'),
+    );
+  }
+
+  function setUp() {
+    parent::setUp('form_test');
+  }
+
+  /**
+   * Test that textfield values are trimmed.
+   */
+  function testTextfieldTrim() {
+    $value = $this->randomName();
+    // Create a form that can be processed and contains a textfield.
+    $form_id = $this->randomName();
+    $form_state = form_state_defaults();
+    $form['textfield'] = array(
+      '#type' => 'textfield',
+    );
+    // Set $value with opening and trailing whitespace as input for the textfield.
+    $form_state['input'] = array(
+      'textfield' => ' ' . $value . ' ',
+      'form_id' => $form_id,
+    );
+    // Prepare and process the form.
+    drupal_prepare_form($form_id, $form, $form_state);
+    drupal_process_form($form_id, $form, $form_state);
+    // Assure that the resulting form value does not contain the whitespace.
+    $this->assertEqual($value, $form_state['values']['textfield'], t('Textfield values are trimmed.'));
+  }
+
+}
+
+/**
  * Test using drupal_form_submit in a batch.
  */
 class FormAPITestCase extends DrupalWebTestCase {
diff --git modules/system/system.admin.inc modules/system/system.admin.inc
index d0b7225..a6f5f38 100644
--- modules/system/system.admin.inc
+++ modules/system/system.admin.inc
@@ -1129,7 +1129,7 @@ function system_ip_blocking_form($form_state) {
 }
 
 function system_ip_blocking_form_validate($form, &$form_state) {
-  $ip = trim($form_state['values']['ip']);
+  $ip = $form_state['values']['ip'];
   if (db_query("SELECT * FROM {blocked_ips} WHERE ip = :ip", array(':ip' => $ip))->fetchField()) {
     form_set_error('ip', t('This IP address is already blocked.'));
   }
@@ -1142,7 +1142,7 @@ function system_ip_blocking_form_validate($form, &$form_state) {
 }
 
 function system_ip_blocking_form_submit($form, &$form_state) {
-  $ip = trim($form_state['values']['ip']);
+  $ip = $form_state['values']['ip'];
   db_insert('blocked_ips')
     ->fields(array('ip' => $ip))
     ->execute();
diff --git modules/taxonomy/taxonomy.module modules/taxonomy/taxonomy.module
index 6bb1da3..d61933d 100644
--- modules/taxonomy/taxonomy.module
+++ modules/taxonomy/taxonomy.module
@@ -217,11 +217,6 @@ function taxonomy_vocabulary_save($vocabulary) {
     $vocabulary->nodes = array();
   }
 
-  if (!empty($vocabulary->name)) {
-    // Prevent leading and trailing spaces in vocabulary names.
-    $vocabulary->name = trim($vocabulary->name);
-  }
-
   if (!isset($vocabulary->module)) {
     $vocabulary->module = 'taxonomy';
   }
@@ -348,10 +343,6 @@ function taxonomy_check_vocabulary_hierarchy($vocabulary, $changed_term) {
  *   Status constant indicating if term was inserted or updated.
  */
 function taxonomy_term_save($term) {
-  if ($term->name) {
-    // Prevent leading and trailing spaces in term names.
-    $term->name = trim($term->name);
-  }
 
   if (!empty($term->tid) && $term->name) {
     $status = drupal_write_record('taxonomy_term_data', $term, 'tid');
diff --git modules/user/user.pages.inc modules/user/user.pages.inc
index def9e06..8d5f173 100644
--- modules/user/user.pages.inc
+++ modules/user/user.pages.inc
@@ -42,7 +42,7 @@ function user_pass() {
 }
 
 function user_pass_validate($form, &$form_state) {
-  $name = trim($form_state['values']['name']);
+  $name = $form_state['values']['name'];
   // Try to load by email.
   $users = user_load_multiple(array(), array('mail' => $name, 'status' => '1'));
   $account = reset($users);