body of email not displaying with attachments in rails2.3.5

I am sending an email through my application to other user’s gmail id. I am receiving email and it works fine without attachment. But when I attach a file, the mail which users receive contain subject and attachments only. The body part is not displaying in the mail. In the controller I am passing everything as params to reminder_email method. I am using rails2.3.5…This is how I have implemented in my mailer.rb file. Please help.

class ReminderMailer < ActionMailer::Base

  def reminder_email(sender,recipients, subject, message,attachments)
    recipient_emails = (recipients.class == String) ? recipients.gsub(' ','').split(',').compact : recipients.compact
    setup_reminder_email(sender, recipient_emails, subject, message,attachments)
  end

  protected
  def setup_reminder_email(sender, emails, subject, message,files)
    @from = sender
    @recipients = emails
    @subject = subject
    @sent_on = Time.now
    @body['message'] = message
    #content_type =  "multipart/alternative"
     files.each do |file|
      attachment "application/octet-stream" do |a|
      a.body = file.read
      a.filename = file.original_filename
    end unless file.blank?
    end
  end
end