Magento- attach file to shipment email?

How can I attach a pdf file to the shipment-email. This wil be the same static file attached to alle shipment emails (gov. required terms).

I have looked into som of the files like dev/lib/mail.php and app/code/cor开发者_如何学JAVAe/Mage/Sales/Model/Email also tried to look at some of the code of the Fooman email attachments extension (wich does not provide the functonality i want), but I'm unsure of how to proceed.

Try something like this.

Mage::getModel('core/email_template')->getMail()->createAttachment(...);

createAttachment(...) method is in Zend_Mail class.

in app/code/core/Mage/Core/Model/Email/Template.php in send method find

$mail->setSubject('=?utf-8?B?' . base64_encode($this->getProcessedTemplateSubject($variables)) . '?='); 
$mail->setFrom($this->getSenderEmail(), $this->getSenderName());

and replace with

if (isset($variables['attachment'])){   
            $attfile = file_get_contents($variables['attachment']); 
            $attfile = fopen($variables['attachment'],'rb');    
            $att = $mail->createAttachment($attfile);   
            //$att->type = 'plain/text';    
            $att->disposition = Zend_Mime::DISPOSITION_ATTACHMENT;  
            $att->filename = $variables['attname']; 
        }   
        $mail->setSubject('=?utf-8?B?' . base64_encode($this->getProcessedTemplateSubject($variables)) . '?=');

        $mail->setFrom($this->getSenderEmail(), $this->getSenderName());