Receive the email attachment in readable format

Hi All,

I tried to send an email with an attachment. I am able to send the
attachment but it is received in the encoded form.

I want to receive the attachment file from my email in the readable
format.

I have the following code for attachment inside my emailer method in the
class that inherits ActionMailer.

attachment :content_type => "image/gif",
        :body => "public/images/header_old.gif"

Should I have to add anything more.

Many thanks in advance.