diff --git a/wp-includes/functions-post.php b/wp-includes/functions-post.php
index 2731befd0470..5f362d5f988b 100644
--- a/wp-includes/functions-post.php
+++ b/wp-includes/functions-post.php
@@ -541,7 +541,8 @@ function do_trackbacks($post_id) {
 	$post = $wpdb->get_row("SELECT * FROM $wpdb->posts WHERE ID = $post_id");
 	$to_ping = get_to_ping($post_id);
 	$pinged  = get_pung($post_id);
-
+	if ( empty($to_ping) )
+		return;
 	if (empty($post->post_excerpt))
 		$excerpt = apply_filters('the_content', $post->post_content);
 	else
@@ -591,7 +592,7 @@ function get_to_ping($post_id) { // Get any URIs in the todo list
 	global $wpdb;
 	$to_ping = $wpdb->get_var("SELECT to_ping FROM $wpdb->posts WHERE ID = $post_id");
 	$to_ping = trim($to_ping);
-	$to_ping = preg_split('/\s/', $to_ping);
+	$to_ping = preg_split('/\s/', $to_ping, -1, PREG_SPLIT_NO_EMPTY);
 	return $to_ping;
 }
 
diff --git a/wp-includes/functions.php b/wp-includes/functions.php
index 012b04877c5e..722f23e1d474 100644
--- a/wp-includes/functions.php
+++ b/wp-includes/functions.php
@@ -633,6 +633,10 @@ function generic_ping($post_id = 0) {
 // Send a Trackback
 function trackback($trackback_url, $title, $excerpt, $ID) {
 	global $wpdb, $wp_version;
+
+	if (empty($trackback_url))
+		return;
+
 	$title = urlencode($title);
 	$excerpt = urlencode($excerpt);
 	$blog_name = urlencode(get_settings('blogname'));
@@ -791,7 +795,7 @@ function do_enclose( $content, $post_ID ) {
 function wp_get_http_headers( $url ) {
 	set_time_limit( 60 ); 
 	$parts = parse_url( $url );
-	$file  = $parts['path'] . $parts['query'];
+	$file  = $parts['path'] . ($parts['query'] ? '?'.$parts['query'] : '');
 	$host  = $parts['host'];
 	if ( !isset( $parts['port'] ) )
 		$parts['port'] = 80;