title: how can I call a webservice from voiceXML?
body: <p>I'm building a very simple voiceXML app to allow people to make recordings.
  But first, I need to authenticate callers by phone number and/or PIN.</p>
  
  <p>Can I call a webservice from voiceXML? Looks like I want to use the voiceXML "data" element to call my webservice. However, I need to dynamically calculate the URL, and it looks like it only takes a static string as the "src" parameter. </p>
  
  <p>I'm new to voiceXML, so pointing me to a good tutorial would help too! I'm working from the voxeo documentation.</p>