The parse_callerid() function not working in

can anyone help me find out why the parse_callerid() in the dtmf.php script -which is part of the phpagi examples is not working ???
what i am trying to get out of asterisk is the callerid phone number. I would really appriciate it…thanks in advance.

<?php set_time_limit(30); require('phpagi.php'); error_reporting(E_ALL); $agi = new AGI(); $agi->answer(); $cid = $agi->parse_callerid(); $agi->text2wav("Hello, {$cid['Number']}."); do { $agi->text2wav('Enter some numbers and then press the pound key. Press 1 1 1 followed by the pound key to quit.'); $result = $agi->get_data('beep', 3000, 20); $keys = $result['result']; $agi->text2wav("You entered $keys"); } while($keys != '111'); $agi->text2wav('Goodbye'); $agi->hangup(); ?>