I'd recommend to extend the classpath settings for JBossAS 7 by these 6 JARs:

1) modules/org/hibernate/validator/main/hibernate-validator-VERSION.jar
-> e.g. @Email, @ScriptAssert
2) modules/org/resteasy/resteasy-jaxrs/main/resteasy-jaxrs-VERSION.jar
-> @Form
3) modules/org/resteasy/resteasy-jaxb-provider/main/resteasy-jaxb-provider-VERSION.jar
-> Provider for XML representations when submitting a GET request for a RESTful webservice
4) modules/org/resteasy/resteasy-multipart-provider/main/resteasy-multipart-provider-VERSION.jar
-> Provider for POST requests with MIME type application/x-www-form-urlencoded
5) modules/org/jboss/logging/main/jboss-logging-VERSION.jar
-> org.jboss.logging.Logger
6) modules/org/picketbox/main/picketbox-VERSION.jar
-> org.jboss.security.*