Index: wp-includes/link-template.php
===================================================================
--- wp-includes/link-template.php	(revision 15489)
+++ wp-includes/link-template.php	(working copy)
@@ -874,18 +874,10 @@
  * @return string
  */
 function get_edit_comment_link( $comment_id = 0 ) {
-	$comment = &get_comment( $comment_id );
-	$post = &get_post( $comment->comment_post_ID );
+	if ( !current_user_can('edit_comment', $comment_id) )
+		return;
 
-	if ( $post->post_type == 'page' ) {
-		if ( !current_user_can( 'edit_page', $post->ID ) )
-			return;
-	} else {
-		if ( !current_user_can( 'edit_post', $post->ID ) )
-			return;
-	}
-
-	$location = admin_url('comment.php?action=editcomment&c=') . $comment->comment_ID;
+	$location = admin_url('comment.php?action=editcomment&c=') . $comment_id;
 	return apply_filters( 'get_edit_comment_link', $location );
 }
 
@@ -900,15 +892,10 @@
  * @return string|null HTML content, if $echo is set to false.
  */
 function edit_comment_link( $link = null, $before = '', $after = '' ) {
-	global $comment, $post;
+	global $comment;
 
-	if ( $post->post_type == 'page' ) {
-		if ( !current_user_can( 'edit_page', $post->ID ) )
-			return;
-	} else {
-		if ( !current_user_can( 'edit_post', $post->ID ) )
-			return;
-	}
+	if ( !current_user_can('edit_comment', $comment->comment_ID) )
+		return;
 
 	if ( null === $link )
 		$link = __('Edit This');
Index: wp-includes/capabilities.php
===================================================================
--- wp-includes/capabilities.php	(revision 15489)
+++ wp-includes/capabilities.php	(working copy)
@@ -990,6 +990,14 @@
 		else
 			$caps[] = 'read_private_pages';
 		break;
+	case 'edit_comment':
+		$caps[] = 'edit_published_posts';
+
+		$comment = get_comment( $args[0] );
+
+		if ( $comment->user_id != $user_id )
+			$caps[] = 'moderate_comments';
+		break;
 	case 'unfiltered_upload':
 		if ( defined('ALLOW_UNFILTERED_UPLOADS') && ALLOW_UNFILTERED_UPLOADS && ( !is_multisite() || is_super_admin( $user_id ) )  )
 			$caps[] = $cap;
Index: wp-admin/includes/dashboard.php
===================================================================
--- wp-admin/includes/dashboard.php	(revision 15489)
+++ wp-admin/includes/dashboard.php	(working copy)
@@ -586,7 +586,7 @@
 	$comment_link = '<a class="comment-link" href="' . esc_url(get_comment_link()) . '">#</a>';
 
 	$actions_string = '';
-	if ( current_user_can('edit_post', $comment->comment_post_ID) ) {
+	if ( current_user_can('edit_comment', $comment->comment_ID) ) {
 		// preorder it: Approve | Reply | Edit | Spam | Trash
 		$actions = array(
 			'approve' => '', 'unapprove' => '',
Index: wp-admin/includes/template.php
===================================================================
--- wp-admin/includes/template.php	(revision 15489)
+++ wp-admin/includes/template.php	(working copy)
@@ -2004,8 +2004,7 @@
 	$comment = get_comment( $comment_id );
 	$post = get_post($comment->comment_post_ID);
 	$the_comment_status = wp_get_comment_status($comment->comment_ID);
-	$post_type_object = get_post_type_object($post->post_type);
-	$user_can = current_user_can($post_type_object->cap->edit_post, $post->ID);
+	$user_can = current_user_can('edit_comment', $comment_id);
 
 	$comment_url = esc_url(get_comment_link($comment->comment_ID));
 	$author_url = get_comment_author_url();
@@ -2025,13 +2024,13 @@
 		$del_nonce = esc_html( '_wpnonce=' . wp_create_nonce( "delete-comment_$comment->comment_ID" ) );
 		$approve_nonce = esc_html( '_wpnonce=' . wp_create_nonce( "approve-comment_$comment->comment_ID" ) );
 
-		$approve_url = esc_url( "comment.php?action=approvecomment&p=$post->ID&c=$comment->comment_ID&$approve_nonce" );
-		$unapprove_url = esc_url( "comment.php?action=unapprovecomment&p=$post->ID&c=$comment->comment_ID&$approve_nonce" );
-		$spam_url = esc_url( "comment.php?action=spamcomment&p=$post->ID&c=$comment->comment_ID&$del_nonce" );
-		$unspam_url = esc_url( "comment.php?action=unspamcomment&p=$post->ID&c=$comment->comment_ID&$del_nonce" );
-		$trash_url = esc_url( "comment.php?action=trashcomment&p=$post->ID&c=$comment->comment_ID&$del_nonce" );
-		$untrash_url = esc_url( "comment.php?action=untrashcomment&p=$post->ID&c=$comment->comment_ID&$del_nonce" );
-		$delete_url = esc_url( "comment.php?action=deletecomment&p=$post->ID&c=$comment->comment_ID&$del_nonce" );
+		$approve_url = esc_url( "comment.php?action=approvecomment&c=$comment->comment_ID&$approve_nonce" );
+		$unapprove_url = esc_url( "comment.php?action=unapprovecomment&c=$comment->comment_ID&$approve_nonce" );
+		$spam_url = esc_url( "comment.php?action=spamcomment&c=$comment->comment_ID&$del_nonce" );
+		$unspam_url = esc_url( "comment.php?action=unspamcomment&c=$comment->comment_ID&$del_nonce" );
+		$trash_url = esc_url( "comment.php?action=trashcomment&c=$comment->comment_ID&$del_nonce" );
+		$untrash_url = esc_url( "comment.php?action=untrashcomment&c=$comment->comment_ID&$del_nonce" );
+		$delete_url = esc_url( "comment.php?action=deletecomment&c=$comment->comment_ID&$del_nonce" );
 	}
 
 	echo "<tr id='comment-$comment->comment_ID' class='$the_comment_status'>";
Index: wp-admin/comment.php
===================================================================
--- wp-admin/comment.php	(revision 15489)
+++ wp-admin/comment.php	(working copy)
@@ -60,8 +60,8 @@
 	if ( !$comment = get_comment( $comment_id ) )
 		comment_footer_die( __('Oops, no comment with this ID.') . sprintf(' <a href="%s">'.__('Go back').'</a>!', 'javascript:history.go(-1)') );
 
-	if ( !current_user_can('edit_post', $comment->comment_post_ID) )
-		comment_footer_die( __('You are not allowed to edit comments on this post.') );
+	if ( !current_user_can('edit_comment', $comment_id) )
+		comment_footer_die( __('You are not allowed to edit this comment.') );
 
 	if ( 'trash' == $comment->comment_approved )
 		comment_footer_die( __('This comment is in the Trash. Please move it out of the Trash if you want to edit it.') );
@@ -84,7 +84,7 @@
 		die();
 	}
 
-	if ( !current_user_can( 'edit_post', $comment->comment_post_ID ) ) {
+	if ( !current_user_can( 'edit_comment', $comment->comment_ID ) ) {
 		wp_redirect( admin_url('edit-comments.php?error=2') );
 		die();
 	}
@@ -184,7 +184,6 @@
 
 <?php wp_nonce_field( $nonce_action ); ?>
 <input type='hidden' name='action' value='<?php echo esc_attr($formaction); ?>' />
-<input type='hidden' name='p' value='<?php echo esc_attr($comment->comment_post_ID); ?>' />
 <input type='hidden' name='c' value='<?php echo esc_attr($comment->comment_ID); ?>' />
 <input type='hidden' name='noredir' value='1' />
 </form>
@@ -212,7 +211,7 @@
 
 	if ( !$comment = get_comment($comment_id) )
 		comment_footer_die( __('Oops, no comment with this ID.') . sprintf(' <a href="%s">'.__('Go back').'</a>!', 'edit-comments.php') );
-	if ( !current_user_can('edit_post', $comment->comment_post_ID ) )
+	if ( !current_user_can('edit_comment', $comment->comment_ID ) )
 		comment_footer_die( __('You are not allowed to edit comments on this post.') );
 
 	if ( '' != wp_get_referer() && ! $noredir && false === strpos(wp_get_referer(), 'comment.php') )