I realize that most people are using XML-RPC as the entire XML document, so namespaces probably don't matter to them. But I'm implementing a job scheduler in which I am separating the scheduling logic from the job handling logic. I do this by defining a job as an XML document consisting of scheduling parameters and an XML-RPC method invocation. When it is time to execute the job, the scheduler acts as an XML-RPC client, making the method call to the job handler process (which is an XML-RPC server). In this context, my job's XML document consists of tags from two namespaces: my job scheduler tags and XML-RPC tags. XML namespaces solve the ambiguity, but XML-RPC doesn't appear to have a well-defined namespace.
Since this is a slighty out-of-the-ordinary usage of XML-RPC, perhaps an example would help illustrate the problem:
<?xml version="1.0" ?>
<!-- Schedules are expressed in ISO-8601 notation. -->
<!-- For example, the following schedule says to
repeat 5 times 1 minute apart, starting on May
18th 2007 at midnight UTC. -->
<value>This is a test</value>
As you can see, currently, I'm just resetting the XML namespace for the XML-RPC
<methodCall>tag (and all nested sub-tags) to an empty namespace. If XML-RPC has a well-defined namespace, however, I would feel much better using that. Please, if anyone is aware of the proper namespace declaration for XML-RPC please let me know. If not, I will gladly offer a unique URL in my personal domain for use as the official XML-RPC identifier: http://www.posi.net/xml-rpc/.