groovy xml-rpc + Services

I'm trying to do some node creation via groovy. Via the XML-RPC groovy module and the Drupal Services module, my groovy code looks like, and results in, this:

groovy:000> def server = new XMLRPCServerProxy("http://localhost/drupal/?q=services/xmlrpc")
ERROR groovy.net.xmlrpc.XMLRPCCallFailureException:
XML-RPC call Failure: fault string = "Empty response from server", fault code = 0
at java_lang_Runnable$run.call (Unknown Source)

'tis a little frustrating not being able to get past the first line of code, but haven't gotten much help from the intertubes.

Anyone here with advice?