php SoapClient and recurring XML

What is the recommended method to create a recurring tag using SoapClient? I'm assuming it's via an array but where does it get the recurring tag name from? And is there any weirdness for a single vs. multiple items?

I'm trying to utilize the Soap layer for开发者_开发知识库 Authorize.Net and it seems to break if I use an array for CustomerPaymentProfileType when there's only one CustomerPaymentProfile in the array.

treii28