hi, I deployed my app to jboss, but something wrong happen: 2007-05-18 22:16:57,843 DEBUG [org.jboss.ejb3.ServiceDelegateWrapper] Starting failed persistence.units:ear=favorites.ear,jar=favoritesEJB.jar ,unitName=favorites java.lang.NullPointerException at org.hibernate.cfg.OneToOneSecondPass.doSecondPass( OneToOneSecondPass.java:135) at org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java :1130) at org.hibernate.cfg.AnnotationConfiguration.secondPassCompile( AnnotationConfiguration.java:296) at org.hibernate.cfg.Configuration.buildMappings(Configuration.java:1115) --- MBeans waiting for other MBeans --- ObjectName: persistence.units:ear=favorites.ear,jar=favoritesEJB.jar ,unitName=favorites State: FAILED Reason: java.lang.NullPointerException I Depend On: jboss.jca:service=DataSourceBinding,name=DefaultDS Depends On Me: jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=AddressFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=AdminFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=CommentFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=FavoritesDirectoryFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=FavoritesFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=PermissionFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=RoleFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=SiteFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=TagFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=UsersFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=UserSiteFacade,service=EJB3 --- MBEANS THAT ARE THE ROOT CAUSE OF THE PROBLEM --- ObjectName: persistence.units:ear=favorites.ear,jar=favoritesEJB.jar ,unitName=favorites State: FAILED Reason: java.lang.NullPointerException I Depend On: jboss.jca:service=DataSourceBinding,name=DefaultDS Depends On Me: jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=AddressFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=AdminFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=CommentFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=FavoritesDirectoryFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=FavoritesFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=PermissionFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=RoleFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=SiteFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=TagFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=UsersFacade,service=EJB3 jboss.j2ee:ear=favorites.ear,jar=favoritesEJB.jar ,name=UserSiteFacade,service=EJB3 here is my code: @Entity @Table(name = "users", catalog = "favorites", uniqueConstraints = {}) public class Users implements java.io.Serializable { private Set<UserSite> userSites = new HashSet<UserSite>(0); //... @OneToMany(cascade = { CascadeType.ALL }, fetch = FetchType.LAZY, mappedBy = "users") public Set<UserSite> getUserSites() { return this.userSites; } public void setUserSites(Set<UserSite> userSites) { this.userSites = userSites; } } @Entity @Table(name = "user_site", catalog = "favorites", uniqueConstraints = {}) public class UserSite implements java.io.Serializable { private Users users; //... @ManyToOne(cascade = {}, fetch = FetchType.LAZY) @JoinColumn(name = "userId", unique = false, nullable = false, insertable = true, updatable = true) public Users getUsers() { return this.users; } public void setUsers(Users users) { this.users = users; } } any advise?