I'm afraid there's no way to do that.
One thing that I can relatively easily do is to report XJC errors and
warnings as Ant's error messages and warning messages. This will
probably let you use "ant -quiet" to suppress all the warnings.
Does this work for you?
regards,
--
Kohsuke KAWAGUCHI 408-276-7063 (x17063)
Sun Microsystems kohsuke.kawaguchi_at_sun.com