problem when a Grails domain class extends from a EJB

When I has a grails domain class User that extends from a UserT class that is an EJB, in the User() instantiation throw an error. I understand not the cause of this problem, please h开发者_如何学Pythonelp me for it and explain me why require the init method and where should be it. The follow is the error code:

Error creating bean with name 'gn.User': Instantiation of bean failed; nested exception is org.springframework.beans.BeanInstantiationException: Could not instantiate bean class [gn.User]: Constructor threw exception; nested exception is java.lang.NoSuchMethodError: com.jobs.users.UserT: method <init>()V not found

Does the super class have a default constructor? I think it needs one.