Index: src/wp-admin/css/colors.css
===================================================================
--- src/wp-admin/css/colors.css	(revision 26823)
+++ src/wp-admin/css/colors.css	(working copy)
@@ -383,13 +383,11 @@
 }
 
 .wrap .add-new-h2,
-.wrap .add-new-h2:active,
-#add-new-comment a {
+.wrap .add-new-h2:active {
 	background: #e0e0e0;
 }
 
-.wrap .add-new-h2:hover,
-#add-new-comment a:hover {
+.wrap .add-new-h2:hover {
 	background: #2ea2cc;
 	color: #fff;
 }
@@ -439,8 +437,7 @@
 	border-color: #c00 !important;
 }
 
-.submit,
-#commentsdiv #add-new-comment {
+.submit {
 	border: none;
 }
 
Index: src/wp-admin/css/wp-admin.css
===================================================================
--- src/wp-admin/css/wp-admin.css	(revision 26823)
+++ src/wp-admin/css/wp-admin.css	(working copy)
@@ -834,8 +834,7 @@
 }
 
 .wrap .add-new-h2,
-.wrap .add-new-h2:active,
-#add-new-comment a {
+.wrap .add-new-h2:active {
 	margin-left: 4px;
 	padding: 4px 8px;
 	position: relative;
@@ -3458,12 +3457,6 @@
 	margin: 0;
 }
 
-#commentsdiv #add-new-comment {
-	border-width: 0 0 1px;
-	border-style: none none solid;
-	margin-top: 6px;
-}
-
 #commentsdiv .comments-box {
 	border: 0 none;
 }
Index: src/wp-admin/includes/meta-boxes.php
===================================================================
--- src/wp-admin/includes/meta-boxes.php	(revision 26823)
+++ src/wp-admin/includes/meta-boxes.php	(working copy)
@@ -555,7 +555,7 @@
 
 	wp_nonce_field( 'get-comments', 'add_comment_nonce', false );
 	?>
-	<p class="hide-if-no-js" id="add-new-comment"><a href="#commentstatusdiv" onclick="commentReply.addcomment(<?php echo $post->ID; ?>);return false;"><?php _e('Add comment'); ?></a></p>
+	<p class="hide-if-no-js" id="add-new-comment"><a class="button" href="#commentstatusdiv" onclick="commentReply.addcomment(<?php echo $post->ID; ?>);return false;"><?php _e('Add comment'); ?></a></p>
 	<?php
 
 	$total = get_comments( array( 'post_id' => $post->ID, 'number' => 1, 'count' => true ) );