Don't output author uri tag if uri is empty.

git-svn-id: http://svn.automattic.com/wordpress/trunk@5699 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/author-template.php

@@ -164,6 +164,10 @@ function the_author_email() {
  */
 function get_the_author_url() {
 	global $authordata;
+
+	if ( 'http://' == $authordata>user_url )
+		return '';
+
 	return $authordata->user_url;
 }
 

wp-includes/feed-atom.php

@@ -26,7 +26,9 @@ $more = 1;
 	<entry>
 		<author>
 			<name><?php the_author() ?></name>
+			<?php $author_url = get_the_author_url(); if ( !empty($author_url) ) : ?>
 			<uri><?php the_author_url()?></uri>
+			<?php endif; ?>
 		</author>
 		<title type="<?php html_type_rss(); ?>"><![CDATA[<?php the_title_rss() ?>]]></title>
 		<link rel="alternate" type="text/html" href="<?php permalink_single_rss() ?>" />