I want to edit the origin field in stock move. If there's a related stock picking object everything is fine. But if I create a new stock move (without a related stock picking object), it's not possible to edit the origin field. (Changes to the field are not stored).

I had a look in class stock_move and found out, that the origin field is no simple char field, but a related field:

'origin': fields.related('picking_id','origin',type='char',size=64, relation="stock.picking", string="Source", store=True) 

Is this the point? My assumption is that there's a problem when no related stock picking object can be found. Looks like a bug for me.

Am I right? Can somebody give me a hint?