Now I'm working on a class to parse DTDs from PHP, Andre Costa is helping me to test the class, after all it was his idea. The class is based on Mike Wukta's DTD parser in Java and seems to be working just fine, it should be ready for a beta release in one or two weeks. Meanwhile I'm still trying to find someone and convince him about porting Jing (A RELAXNG validator) from Java to PHP. If you are interested just drop me a note or send me an email (there's a contact link from the sourceforge home of the phpxmlclasses project)