We use the xmltask ANT task for conditional logic (ie: if statements) in our ANT scripts.
Currently this task is bombing, apparently because can't reach "http://java.sun.com/dtd/application_1_3.dtd". We can't access this URL either in our browser. Has Sun "deprecated" these Java DTD URL's?
Update: Appears http://java.sun.com/ is not available either. Not sure if this is a outage on Sun/Oracle's end or if this site has been decommissioned.
Update 2: Ok, now it is working. Hasn't been working since yesterday - I swear! I think @Jeremy is right we need to host this ourselves.
I suggest you just download it and host it yourself.