I have some problems with onetoone mapping: May someone tell me whats wrong? Here is the short version: Tables and References: Test <------> Test2 PK/FK id <--> PK id e.g. public class Test{ .... @ID private String id; //PK and FK @OneToOne protected Test2 test2; .... public class Test2{ ... @ID private String id; //PK, so that id of Test2 is the same as id of Test1 ..... This way I'm getting problems by creating an entitymanager and working with Test I think.... THX for help! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3990481#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...