[Haskell-cafe] xml packages

First question. As I saw in sources, both hxt and haxml uses [Char]'s. this is very inefficient. I want to know, does any effective parser for haskell, written in haskell, exists. Efficient means using ByteString to store strings and possibly building representations that shares one string for all similiary named elements. If there is no, is anyone interested in writing one? Second question. I'd like to have a package for read-write-edit SVG graphics. I think, xslt (both transformations and formatting object) are interesting too. Is anyone considering writing such packages?