soap segmentation fault using wsdl file in PHP

[don2241]

Hi,
I have a simple test snippet below.
When I run this in PHP 5.1.6 I get a Segmentation Fault error but when I run the exact same code in PHP 5.3.3 everything works fine. The error appears to happen on this line:
$obj = $soap->retrievePrice($arr);

If I do not want to upgrade the PHP version what do I need to do to make this work in PHP v.5.1.6
Can anyone point me in the right direction

/Martin

**** start code ****
$soap = new SoapClient("file.wsdl");
$arr = array(
"faci" =>"M00",
"itno" =>"VISIA",
"cuno" =>"100000",
"cucd" =>"AUD"
);
try{
$obj = $soap->retrievePrice($arr);
$result = (array)$obj;
print_r($result);
}
catch (SoapFault $exception){
echo $exception;
}
**** finish code ****