Index: wp-includes/shortcodes.php
===================================================================
--- wp-includes/shortcodes.php	(revision 1384)
+++ wp-includes/shortcodes.php	(working copy)
@@ -175,7 +175,7 @@
 	$tagnames = array_keys($shortcode_tags);
 	$tagregexp = join( '|', array_map('preg_quote', $tagnames) );
 
-	return '(.?)\[('.$tagregexp.')\b(.*?)(?:(\/))?\](?:(.+?)\[\/\2\])?(.?)';
+	return '(.?)\[('.$tagregexp.')\b([^\[\]\r\n]*?)(?:(\/))?\](?:(.+?)\[\/\2\])?(.?)';
 }
 
 /**