From what I know, JBoss WS uses org.jboss.ejb3.common.resolvers.spi.EjbReferenceResolver for resolving @EJB injections. This package has now been deprecated. Instead a new jboss-ejb3-ejbref-resolver has been created to handle this resolution. This new SPI and implementation has been integrated into AS trunk. The older version of the resolver won't be able to handle EJB3.1 nointerface view.
It's recommended that JBoss WS move to this new SPI. The semantics of the EjbReferenceResolver are the same as before, except that it's been moved to a new package now. More details here http://community.jboss.org/message/558875#558875 including a link to the wiki.