How do I login a user with devise?

I have my rails application and I am running into a major issue with devise. I have a controller:

class Users::SessionsController < Devise::SessionsController
  prepend_before_filter :require_no_authentication, :only => [ :new, :create ]
  include Devise::Controllers::InternalHelpers

def new
    clean_up_passwords(build_resource)

    respond_to do |format|
      format.html { render :layout => "sessions" }
      format.mobile
    end
  end


    # POST /resource/sign_in
    def create
      resource = User.find_by_email(params[:user][:email])  
      resource = warden.authenticate!(:scope => resource_name, :recall => "#{controller_path}#new")
      set_flash_message :notice, :signed_in
      sign_in_and_redirect(resource_name, resource)
    end

end

The problem is it never logs the user in, it always stops at this line

resource = warden.authenticate!(:scope => resource_name, :recall => "#{controller_path}#new")

I even put tons of loggers in the actual gem files to see if I could see anything off but nothing and I really have no idea how to fix this. If I comment this line out then the user gets logged in but fails if the email is not in the db and works for any password (which is definitely not the right solution)

How do I fix this?

UPDATE

this works but seems very hackish

# POST /resource/sign_in
def create
  resource = User.find_by_email(params[:user][:email])

  redirect_to(new_user_session_path, :notice => 'Invalid Email Address or Password. Password is case sensitive.') and return if resource.encrypted_password.blank?      
  bcrypt   = BCrypt::Password.new(resource.encrypted_password)
  password = BCrypt::Engine.hash_secret("#{params[:user][:password]}#{resource.class.pepper}", bcrypt.salt)
  valid = Devise.secure_compare(password, resource.encrypted_password)
 # resource = warden.authenticate!(:scope => resource_name, :r