@JoinColumn(foreignKey = @ForeignKey(ConstraintMode.NO_CONSTRAINT))

hibernate will still try to add constraint

2013-12-18 11:25:37,036 localhost-startStop-1 org.hibernate.tool.hbm2ddl.SchemaUpdate ERROR HHH000388: Unsuccessful: alter table oauth_client add constraint FK_43dmxuh3574xhqwmvkt8gdwqf foreign key (owner) references `user` (id)