try using the
tag (put it on your facelet template and then you never have to worry about your document declarations) If still having problems, you might want to try the ICEfaces forum at http://www.icefaces.org/JForum/forums/list.page
Thanks, judy, for your reply.
Sadly, your first idea did not work out. Nevertheless, searching through the icefaces forum I stumbled upon two threads focussing on the same issue:
As both suggestions to fix the problem did not work for me I implemented a custom HttpServletResponseWrapper, called via an HttpServletFilter configured in the web.xml, that prepends the doctype declaration if needed.