problem with Resque

I am trying to install Resque on my Rails application, following the Railscast http://railscasts.com/episodes/271-resq … =asciicast

I have installed Redis and Resque successfully.

From my controller I am calling:

Resque.enqueue(UserCreator, @user.id)

I receive the call at the UserCreator class at the perform method:

class UserCreator
  @queue = :users_queue
  def self.perform(user_id)

    user_obj = User.find(user_id)

  end
end

However the following delayed job fails, and gives an error within Resque admin:

Class: UserCreator
Arguments: 8
Exception: ActiveRecord::StatementInvalid
Error: PG::Error: ERROR: prepared statement