Mobile commerce handler

You need to write a handler for mobile commerce service from x-bill
The handler must be on php. After confirming the payment by the subscriber, the processor must send the password from the text file, the passwords I write manually in the text file, there is an old processor, I can provide to completely not write the code, it is fully working, sends the password and deletes it from the text file, so the password is always unique, but the processor works with sms billing, and I decided to connect to mobile commerce. The performer is required to have competent and optimized code, detailed comments throughout the code, as well as the following. In the future, I will connect the processor in the flash application. I will provide all the information that is needed to write a script. I have been working with PHP for a long time, so the complexity of the work is not so high, an experienced programmer will perform the work in an hour, especially all kinds of source and examples of processors will be provided from the above site. Payment is contractual, I expect an adequate cost.