Override devise registrations controller

I have added a field to the sign-up form that is based on a different model, see How do I use nested attributes with the devise model for the gory details. This part is working fine. The problem now is when I save, it is failing in the create action of the registrations controller that is supplied by devise with an Activerecord::UnknownAttributeError on this field (company). I am assuming I need t

[takaesu]

deviseで利用するcontrollerのオーバーライド方法