PHP SOAP Client formats

Hi all, ok, I am a little bit new to the SOAP game, but I understand it, and am using it to talk to an outside API. The problem that I have is that the server that I am talking to (that is not in my control), will accept the following SOAP call <?xml version="1.0" encoding="utf-8"?> <soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"> <soap:Body> <AuthenticateTest xmlns="https://api.authorize.net/soap/v1/">

     <merchantAuthentication>
       <name>name</name>
       <transactionKey>string</transactionKey>
     </merchantAuthentication>

</AuthenticateTest> </soap:Body> </soap:Envelope> But it refuses a call that I have made using the SOAPClient PHP classes that look like this : <?xml version="1.0" encoding="UTF-8"?> <SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ns1="https://api.authorize.net/soap/v1/"> <SOAP-ENV:Body> <ns1:AuthenticateTest>

     <merchantAuthentication>
       <name>name</name>
       <transactionKey>string</transactionKey>
     </merchantAuthentication>

</ns1:AuthenticateTest> </SOAP-ENV:Body> </SOAP-ENV:Envelope> It appears that the one that PHP creates is all in line with all of the latest standards, and I know that the server is a Microsoft IIS server. Does anyone know any parameters that I can use with the PHP SOAP client that could help me contruct the request like the top one??? I don't want to have to build the text myself, and open a socket and send the text manually like I did to verify that the top one works, and the bottom one doesn't. Thanks, Tim.