Cannot originate calls on Asterisk 11

After upgrading our VoIP server into FreePBX with asterisk 11 we
faced an issue relating queXS behavior: queXS could connect and
monitor as normal, but was totally unable to make any call, and it
also lacked any kind of log or response about what was happening at
the time. Many hours of work later, we found the problem and
implemented a provisional solution in our limited understanding of the
issue at hand:
We edited the line 190 in functions/functions.voip.php from:

   $r = $this->query("Action: Originate\r\nChannel: $ext\r\nExten: $number\r\nPriority: 1\r\nCallerid: $ext\r\n\r\n","Response");

to:

   $r = $this->query("Action: Originate\r\nChannel: $ext\r\nExten: $number\r\nContext: XXXXX\r\nPriority: 1\r\nCallerid: $ext\r\n\r\n","Response");