diff --git a/core/modules/filter/filter.test b/core/modules/filter/filter.test
index 2bafd47..8913dec 100644
--- a/core/modules/filter/filter.test
+++ b/core/modules/filter/filter.test
@@ -1101,6 +1101,10 @@ class FilterUnitTestCase extends DrupalUnitTestCase {
 
     $f = _filter_html('<code onerror>&nbsp;</code>', $filter);
     $this->assertNoNormalized($f, 'onerror', t('HTML filter should remove empty on* attributes on default.'));
+
+    // The HTML filter should allow the <!--break--> tag.
+    $f = _filter_html('teaser <!--break--> body', $filter);
+    $this->assertIdentical($f, 'teaser <!--break--> body', 'HTML filter should not remove the &lt;!--break--&gt; tag.');
   }
 
   /**
diff --git a/core/modules/node/node.test b/core/modules/node/node.test
index f828164..068b4cd 100644
--- a/core/modules/node/node.test
+++ b/core/modules/node/node.test
@@ -624,6 +624,45 @@ class SummaryLengthTestCase extends DrupalWebTestCase {
   }
 }
 
+/**
+ * Tests the node summary break separator.
+ */
+class SummaryBreakTestCase extends DrupalWebTestCase {
+  public static function getInfo() {
+    return array(
+      'name' => 'Summary break',
+      'description' => 'Test the summary break separator.',
+      'group' => 'Node',
+    );
+  }
+
+  /**
+   * Tests that the <!--break--> separator properly delimits the summary.
+   */
+  function testSummaryBreak() {
+    // Create a node to view.
+    $settings = array(
+      'body' => array(LANGUAGE_NONE => array(array('value' => 'Lorem ipsum dolor sit amet<!--break-->consectetur adipiscing elit.'))),
+      'promote' => 1,
+    );
+    $node = $this->drupalCreateNode($settings);
+
+    // Create user with permission to view the node.
+    $web_user = $this->drupalCreateUser(array('access content'));
+    $this->drupalLogin($web_user);
+
+    // Check for the node's teaser on the promoted node listing.
+    $this->drupalGet('node');
+    $this->assertRaw('Lorem ipsum dolor sit amet', 'The node summary is found.');
+    $this->assertNoRaw('consectetur adipiscing elit.', 'Text after the break separator is not found.');
+
+    // Check the text on the full node page.
+    $this->drupalGet('node/' . $node->nid);
+    $this->assertRaw('Lorem ipsum dolor sit amet', 'The node summary is found.');
+    $this->assertRaw('consectetur adipiscing elit.', 'Text after the break separator is found.');
+  }
+}
+
 class NodeTitleXSSTestCase extends DrupalWebTestCase {
   public static function getInfo() {
     return array(