diff --git a/modules/comment/comment.module b/modules/comment/comment.module
index b52204a..395bb63 100644
--- a/modules/comment/comment.module
+++ b/modules/comment/comment.module
@@ -2285,7 +2285,7 @@ function template_preprocess_comment(&$variables) {
     $variables['status'] = ($comment->status == COMMENT_NOT_PUBLISHED) ? 'comment-unpublished' : 'comment-published';
   }
   // Gather comment classes.
-  if ($comment->uid === 0) {
+  if ($comment->uid == 0) {
     $variables['classes_array'][] = 'comment-by-anonymous';
   }
   else {
diff --git a/modules/comment/comment.test b/modules/comment/comment.test
index e5cae5e..882c195 100644
--- a/modules/comment/comment.test
+++ b/modules/comment/comment.test
@@ -331,6 +331,8 @@ class CommentInterfaceTest extends CommentHelperCase {
     $comment = $this->postComment($this->node, $comment_text);
     $comment_loaded = comment_load($comment->id);
     $this->assertTrue($this->commentExists($comment), t('Comment found.'));
+    $by_viewer_class = $this->xpath('//div[contains(@class, "comment-by-viewer")]');
+    $this->assertTrue(!empty($by_viewer_class), t('HTML class for comments by viewer found.'));
 
     // Set comments to have subject and preview to required.
     $this->drupalLogout();
@@ -417,6 +419,13 @@ class CommentInterfaceTest extends CommentHelperCase {
     $this->assertTrue($this->commentExists($reply, TRUE), t('Page two exists. %s'));
     $this->setCommentsPerPage(50);
 
+    // Create comment #5 to assert HTML class.
+    $this->drupalLogout();
+    $this->drupalLogin($this->admin_user);
+    $comment = $this->postComment($this->node, $this->randomName(), $this->randomName());
+    $by_node_author_class = $this->xpath('//div[contains(@class, "comment-by-node-author")]');
+    $this->assertTrue(!empty($by_node_author_class), t('HTML class for node author found.'));
+
     // Attempt to post to node with comments disabled.
     $this->node = $this->drupalCreateNode(array('type' => 'article', 'promote' => 1, 'comment' => COMMENT_NODE_HIDDEN));
     $this->assertTrue($this->node, t('Article node created.'));
@@ -963,6 +972,8 @@ class CommentAnonymous extends CommentHelperCase {
     // Post anonymous comment without contact info.
     $anonymous_comment1 = $this->postComment($this->node, $this->randomName(), $this->randomName());
     $this->assertTrue($this->commentExists($anonymous_comment1), t('Anonymous comment without contact info found.'));
+    $anonymous_class = $this->xpath('//div[contains(@class, "comment-by-anonymous")]');
+    $this->assertTrue(!empty($anonymous_class), t('HTML class for anonymous comments found.'));
 
     // Allow contact info.
     $this->drupalLogin($this->admin_user);