Sorry, my post above was not well formed
There is updated
I found that Seam2.0 documentation advices to put "exception" tag to pages.xml.
It does not work!
Moreover, if you open Pages.java that you can see that "exception" tags are not parsed at all!
Exception.java parses exceptions.xml which marked as deprecated.
What I'm doing wrong?
In pages.xml, they are parsed by Exceptions.java from there.
Really, just next row under deprecated file parsing!
Thanks Pete, I'm very-very ashamed :((