What version of Seam do you use?
the last one : jboss-seam-1.2.1.GA
(btw, this version 1.2.1 still writes "Welcome to Seam 1.2.0.PATCH1" on load ;-) )
same problem if I start my jboss server with my seam application without having my laptop connected to the internet :
Caused by: org.dom4j.DocumentException: jboss.com Nested exception: jboss.com
So, update your xml files to use the 1.2 DTDs/XSDs - these are distributed with Seam so it doesn't matter whether there is a net connection
Thanks a lot ... it did the trick ... and I understood the problem ... I'll be more careful during the next seam version change ;-)