agntdrake: The perl module you're looking for is XML::Simple. Very (!) easy to translate from a hashref of whatever (arrays, hashrefs, scalars) to XML and back again. The only slightly annoying thing is that it represents almost everything as XML name keys (<key name1="val" name2="val2">) versus the way you describe. It's all valid XML, but one is easier (IMO) to hand-edit than the other, which is a legit concern when you're using it for configuration files.
(Originally posted elsewhere)