Web service is giving "illegal refid function"

We are calling a PHP web service from a Rails app using RPC. This was working fine. We had some offshore PHP programmers modify the web service and now this portion of the app throws an error that says illegal refid function.require-once.

Having never used RPC before, I am just a tiny bit confused. This would be an e开发者_运维问答rror with the PHP code that the RPC is calling, correct? I know PHP has a require_once function.

It looks like it, but without looking at the actual code (of the web service) and input (your HTTP request), this question cannot be answered.