Why does simple_format not work in a rake task?

incoming_mail.rake

require "rubygems"
require "bundler/setup"
require "mailman"
require 'active_support/inflections'
require 'action_view/helpers'

extend ActionView::Helpers

namespace :incoming_mail do

  ENV["RAILS_ENV"] ||= "test"
  require File.dirname(__FILE__) + "/../../config/environment"

  Mailman.config.ignore_stdin = true
  Mailman.config.logger = Logger.new File.expand_path("../../../log/mailman_#{Rails.env}.log", __FILE__)

  task :readmail => :environment do
    if Rails.env == 'test'
      Mailman.config.maildir = File.expand_path("../../../tmp/test_maildir", __FILE__)
    else
      Mailman.config.logger = Logger.new File.expand_path("../../../log/mailman.log", __FILE__)
      Mailman.config.poll_interval = 120

      Mailman.config.pop3 = {
        server: 'pop.gmail.com', port: 995, ssl: true,
        username: MAIL_USER,
        password: MAIL_PASSWORD
      }
    end  

    Mailman::Application.run do
      default do
        process_message(message)
      end  
    end

  end

end


def process_message(message)

  puts message.to.to_s

  if message.multipart?
    message_txt = message.parts[0].body
  else
    message_txt =  message.body
  end

  message_filtered = Array.new

  message_txt.to_s.split("\n").each do |line|
    if line[0] != ">" and !line["wrote:"]
      message_filtered.push line
    end
  end

  fmessage = message_filtered.join("\n")

  uuid = message.to.to_s.match("[a-f0-9]{8}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{4}-[a-f0-9]{12}").to_s
  
  if uuid.empty?
    if Ticket.where(:email => message.from.first.to_s).count > 0 then # has email been used for tickets before?
      puts "New ticket"
      ticket = Ticket.new
      ticket.title = message.subject.to_s
      ticket.problem = simple_format(fmessage)
      ticket.email = message.from.to_s
      ticket.fbid = 0
      ticket.player_id = 0
      ticket.resolved = false

      ticket.game_id = Ticket.where(:email => message.from.first.to_s).first.game_id
      ticket.save
      
      SupportMailer.welcome_email(ticket).deliver
    end
  else 
    new_message = Message.new
    new_message.title = message.subject
    new_message.content = simple_format(fmessage)
    new_message.token = uuid
    new_message.save
  
    puts "New message:#{uuid.to_s}"  
  end
end