Help using secure SOAP service PHP

Fellow programmer needs help on consuming web service for related project. Provider has sent WSDL link, .pem certificate and passphrase. Service functionality is to upload a zip file. I need a programmer to come up with a working PHP script using either PHP Soap or NuSoap or any free library that allows me to consume web service. If problem would reside with SOAP provider, I would act as liaison and the selected coder would have to get the script working after detecting this. I'm new to SOAP with security certificates, so I'm unable to do this; however it's a very simple project for someone who has worked with this before. Final script is probably less that 30 lines. **NOTE: I'm talking about client side SOAP, NOT creating a SOAP Server ****