This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
The "id" attribute is special. It's actually part of the core XML spec, and it carries a constraint: Each id value in an XML file MUST be unique. This is true whether the XML is JSF, SOAP, or any random XML format you may device.
So your original xhtml should have failed XML validation and that means that effectively JBoss has fixed a bug.
Customer surveys are for companies who didn't pay proper attention to begin with.