Also, declaring `@ManyToMany` like this creates a join table with a super weird name. Try to use the `@JoinTable` annotation too to set a more reasonable name. E.g.:

    @JoinTable(name="account_queue",
        joinColumns=
            @JoinColumn(name="account_id", referencedColumnName="id"),
        inverseJoinColumns=
            @JoinColumn(name="queue_id", referencedColumnName="id"))