Index: wp-includes/comment.php
===================================================================
--- wp-includes/comment.php	(revision 20788)
+++ wp-includes/comment.php	(working copy)
@@ -1812,6 +1812,11 @@
 	do_action_ref_array( 'pre_ping', array( &$post_links, &$pung, $post_ID ) );
 
 	foreach ( (array) $post_links as $pagelinkedto ) {
+		$url = parse_url( $pagelinkedto );
+		if ( !empty( $url['fragment'] ) ) {
+			unset( $url['fragment'] );
+			$pagelinkedto = implode( '', $url );
+		}
 		$pingback_server_url = discover_pingback_server_uri( $pagelinkedto );
 
 		if ( $pingback_server_url ) {