[Zope] XML from external server

Would appreciate your opinion: I have an external web server that replies to a certain request with an XML file, with a well defined structure. My goal is to have Zope pick up this file, and "do stuff" with it: perhaps return the HTML after applying an XSLT, or - ideally - access its contents (or parts of it) from some page template and/or DTML. The XML data (but not structure) may change quite often, independently of Zope, and I'd like these changes to be visible to the Zope clients, so it's not only a matter of storing the XML once. Anybody done anything like it? Hints? Tips? Gotchas? Examples? Products?!? -- Robert Segall Apsis GmbH Postfach, Uetikon am See, CH-8707 Tel: +41-44-920 4904