Hi,
There is a lot of hidden issues in doing this with PHP. In my experience the certificate should have no passphrase and some other environment-dependent things. Could you let me try it without charging you? Just send me the certificate, the request and which URL I should send it to check if it works - I will play with options and let you know if it works and then you award it. I just don't want to promise what will fail.
Thanks,
Sergei