can you help me, it looks like you know alot about php, im running this php script and for some reason im getting this error:

Warning: Call-time pass-by-reference has been deprecated; If you would like to pass it by reference, modify the declaration of xml_parse_into_struct(). If you would like to enable call-time pass-by-reference, you can set allow_call_time_pass_reference to true in your INI file. in /home/web/script/aws4class.php on line 255

i tried to figure it but i gave up