I have PHP 5.3.8 and the error I get is on this line:
array_unshift($this->parents, &$this->parent);
The value of $this->parent comes from:
$this->parent[$key] = array();
$this->parent = &$this->parent[$key];
The error message is:
Deprecated: Call-time pass-by-reference has been deprecated in /var/www/vhosts/mauilistings.net/httpdocs/xml/kd_xmlrpc.php on line 136
Taking off the & sign does not help, the function no longer works.
array_unshiftshould still work, however you might need to change some other function as well. - hakre