Is there a way to encourage CiviCRM to use an outbound proxy that is set system-wide for PHP applications? This is the format of our config in /etc/php/set_proxy.php:

<?php
$stream_default_opts = array(
  'http'=>array(
    'proxy'=>"tcp://proxy.example.com:8118",
    'request_fulluri' => true,
 ),
  'https'=>array(
    'proxy'=>"tcp://proxy.example.com:8118",
    'request_fulluri' => true,
 )
);

stream_context_set_default($stream_default_opts);

putenv('http_proxy=http://proxy.example.com:8118');
putenv('https_proxy=http://proxy.example.com:8118');
?>

However CiviCRM seems to ignore this setting at least some of the time: #324