I've never done anything with XML in any language, but HaXml is probably what you're looking for in Haskell. (see also an introductory article to HaXml -- Transcending the limits of DOM, SAX, and XSLT). And GHC is the industrial grade compiler for Haskell, written, of course, in Haskell. It is much faster than Hugs.
-- All code is 100% tested and functional unless otherwise noted.