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I'm afraid that there's no way to override the
JSF default attribute values. You could define a composite control, although for consistency's sake I normally place the h:messages element in a fixed zone on the page layout (using Facelets). Meaning that I don't have multiple definitions of the messages tag, since the same copy is used for all invocations of the page template.
The secret of how to be miserable is to constantly expect things are going to happen the way that they are "supposed" to happen.
You can have faith, which carries the understanding that you may be disappointed. Then there's being a willfully-blind idiot, which virtually guarantees it.