Remove your new code and update $url['host'] and $url['port'] so that they correspond to your new settings.
You should have the following set before calling fsockopen:
PHP Code:
$url['host'] = 'yourproxyaddress';
$url['port'] = '3128';
The reason your new code is not working is because the variables $url['proxy.proxy.proxy.com.au'] and $url['3128'] do not exist. What I think you were trying to achieve is: fsockopen('proxy.proxy.proxy.com.au', '3128', $errno, $errstr, 5);