WCF over HTTPS with PHP throwing "Method not allowed" exception

I created a WCF.NET service that should always be over HTTPS. When I first created the service skeleton and ran it over HTTP it worked fine. I used PHP5 to test for compatibility with built-in SOAP functions. However, once I switched to HTTPS, when I try to call a function from PHP, I get an error with the message "Method Not Allowed" and the error code "http". However, this allows me to get a list of methods. The error occurs when calling the Test method.

Here is the WCF config:

  <system.serviceModel>
    <bindings>
      <basicHttpBinding>
        <binding name="secureBasic">
          <security mode="Transport">
            <transport clientCredentialType="None" />
          </security>
        </binding>
      </basicHttpBinding>
    </bindings>
    <services>
      <service behaviorConfiguration="apiBehavior" name="TestAPI.API">
        <endpoint address="https://192.168.0.3/API" 
                  binding="basicHttpBinding" 
                  bindingConfiguration="secureBasic" 
                  contract="TestAPI.IAPI"/>
        <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="apiBehavior">
          <serviceMetadata httpGetEnabled="true" httpsGetEnabled="true"/>
        </behavior>
      </serviceBehaviors>
    </behaviors>
  </system.serviceModel>

      

        
        
        
      

    

And this is what PHP calls it:

$client = new SoapClient("https://192.168.0.3/API.svc?wsdl");
echo "<pre>" . print_r($client->__getFunctions(), 1) . "</pre>";
$param = new stdClass();
$param->A = "123";
$param->B = "456";
try {
    $client->Test($param);
} catch (Exception $e) {
    die("<pre>" . print_r($e,1) . "</pre>");
}

      

        
        
        
      

    

I am using a self signed SSL certificate for testing and I do not believe PHP requires a trusted certificate.

What am I doing wrong?