It is being worked on, will be included in future updates to the documentation.
I found some vage information in the old JBoss3.0QuickStart document. Of course, it is very much incomplete. They mostly talk about what is XML and what is WSDL and almost nothing about how all these are implemented in JBoss.
I was about to buy the full documentation (yes, I actually thought it would say more about webservices than in the old, free document). It's good to know that it would've been a waste of money ...
I found this site. I havent tried it yet but it is more than I can find on Web-Services anywhere else. And I do have the subscription.
If you are new to JBoss or just the parts that you can't find examples for (XDoclet) it is worth a look.
Be sure to scan the JBoss.Net one through to the end before coding as he has some updates for 3.2.2
Hope this helps.