Index: wp-includes/functions.php
===================================================================
--- wp-includes/functions.php	(revision 28219)
+++ wp-includes/functions.php	(working copy)
@@ -643,7 +643,20 @@
 	return _http_build_query( $data, null, '&', '', false );
 }
 
-// from php.net (modified by Mark Jaquith to behave like the native PHP5 function)
+/**
+ * From php.net (modified by Mark Jaquith to behave like the native PHP5 function).
+ *
+ * @since 3.2.0
+ * @link  http://us1.php.net/manual/en/function.http-build-query.php
+ *
+ * @param array|object  $data An array or object of data. Converted to array.
+ * @param string 		$prefix Optional. Numeric index. If set, start parameter numbering with it.
+ * @param string 		$sep Optional. Argument separator; defaults to 'arg_separator.output'.
+ * @param string 		$key Optional. Used to prefix key name.
+ * @param bool 			$urlencode Optional. Whether to use {@link urlencode()} in the result.
+ *
+ * @return string The query string.
+ */
 function _http_build_query($data, $prefix=null, $sep=null, $key='', $urlencode=true) {
 	$ret = array();