A minor glitch:
The trackback URL that is displayed by the weblog_trackbacks($id) tag contains an ampersand that is not encoded as an entity.
Suggested fix for 2.4.004: in pm/lib/weblog.fns.php, change line 3081 from
$trackback_url = $pingserver_path."?p=tb&id=$id";
to
$trackback_url = $pingserver_path."?p=tb&id=$id";
