I'm using Hibernate 3.2CR1, which is shipped with JBoss 4.0.4 GA (or is it Hibernate 3.2CR2?). There is an entity with an embedded class, and the latest has some @ManyToMany mappings with optional=true. When I do a query like "select obj.x, obj.y from MyClass obj where obj.id=:id", the generated SQL query has inner joins as if the embedded many-to-one associations had optional=false. I added nullable=true to the @JoinTable but nothing changed. Do you have any idea of what is going on?