Version 1 of the API is now deprecated

i found it:

First, make sure you got the new embedded timeline (widget) code fromhttps://twitter.com/settings/widgets/new

so...

FIX here:

replace

<script type="text/javascript" src="http://twitter.com/statuses/user_timeline/<?php echo $username; ?>.json?callback=twitterCallback2&count=<?php echo $num; ?>"></script>

with

<script type="text/javascript" src="https://api.twitter.com/1/statuses/user_timeline/<?php echo $username; ?>.json?callback=twitterCallback2&count=<?php echo $num; ?>"></script>

Pull request here: https://github.com/Elgg/Elgg/pull/414