Index: wp-includes/formatting.php
===================================================================
--- wp-includes/formatting.php	(revision 9823)
+++ wp-includes/formatting.php	(working copy)
@@ -1035,7 +1035,7 @@
 function make_clickable($ret) {
 	$ret = ' ' . $ret;
 	// in testing, using arrays here was found to be faster
-	$ret = preg_replace_callback('#([\s>])([\w]+?://[\w\\x80-\\xff\#$%&~/.\-;:=,?@\[\]+]*)#is', '_make_url_clickable_cb', $ret);
+	$ret = preg_replace_callback('#([\s>])([\w]+?://[\w\\x80-\\xff\#$%&~/.\-;:=,?@\[\]()+]*)#is', '_make_url_clickable_cb', $ret);
 	$ret = preg_replace_callback('#([\s>])((www|ftp)\.[\w\\x80-\\xff\#$%&~/.\-;:=,?@\[\]+]*)#is', '_make_web_ftp_clickable_cb', $ret);
 	$ret = preg_replace_callback('#([\s>])([.0-9a-z_+-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})#i', '_make_email_clickable_cb', $ret);
 	// this one is not in an array because we need it to run last, for cleanup of accidental links within links