SoapClient attributes on called function element - php

Question

How can I add attributes to the XML node of the soap method I call via SoapClient?
Long story ->
I want to get an authentication token from Zimbra via the SOAP API (https://files.zimbra.com/docs/soap_api/8.6.0/api-reference/zimbraAdmin/Auth.html). I can do it when I build the soap xml by myself
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:urn="urn:zimbra" xmlns:urn1="urn:zimbraAdmin">
<soapenv:Header>
<urn:context />
</soapenv:Header>
<soapenv:Body>
<urn1:AuthRequest name="'. $user .'" password="'. $password .'" />
</soapenv:Body>
</soapenv:Envelope>
But I can't get the name and password attributes as attributes on the AuthRequest (the soap endpoint I am calling) when using SoapClient:
$soap = new SoapClient(ZIMBRA_WSDL, array('trace' => true));
$result = $soap->authRequest(
array(
new SoapParam(ZIMBRA_ADMIN, 'account'),
new SoapParam(ZIMBRA_PASSWORD, 'password')
)
);
It produces always new child elements for AuthRequest whatever I'm trying.
Anybody can help?
I tried lot of recommendations w/o any success.

Answer 1

The problem was that there are two methods authRequest in different namespaces. I've changed the WSDL url to only retrieve the zimbraAdmin endpoint and then SoapClient was able to fill the request correct via:
$result = $soap->authRequest(
array(
'name' => $user,
'password' => $password
)
);