probably that object has a foreign key with another objects. You should remove from that list,I think.
You're right, the ManyToOne didn't have any cascade attribute set.
Adding the CascadeType.ALL made the stuff work.
It's a one-to-one in fact here, so I can cascade the remove, not sure what to do if it's really a many-to-one, set explicitly to cascade none ?
Sounds weird ...
Isn't cascade=none the default value for binding ?