model - rails belongs_to foreign key is null -

i have following models

class user     has_many :projects, :through => :bids has_many :bids, :dependent => :destroy end  class project attr_accessible :name, :user_id  has_many :users, :through => :bids has_many :bids, :dependent => :destroy  belongs_to :projectmanager, :class_name => "user", :foreign_key => "user_id"  end  class bid attr_accessible :project_id, user_id belongs_to :user belongs_to :project end 

as can see, project class has both *has_many* , *belongs_to* same model (user)

in project controller new have

def new @project = project.new @project.gencontr = current_user 

where current_user devise current logged in user.

when save project, column user_id in projects table null. can show me go wrong on one...thank you

on create action

def create   @project = project.new(prams[:project])   @project.projectmanager = current_user   ....... end