We love using Email Integration, but found a little nasty bug in product-emailreplyint.xml on line 1050 which puts the variable $encoding in the headers instead of it's value. Which causes many mailservers to bounce the e-mails sent.
Code:
$eiheaders .= 'Content-Transfer-Encoding: $encoding' . $delimiter;
The bug can be fixed by changing the single quotes ( ' ) to double quotes ( " )
Code:
$eiheaders .= "Content-Transfer-Encoding: $encoding" . $delimiter;