How can I check the content transfer encoding of incoming emails using Zend framework

How can I detect the content-transfer-encoding of emails in the inbox using Zend framework.

I need to check to make sure whether a message is qyoted printable content so I can run a decode upon it somehow. The en开发者_如何学运维coding doesn't appear in the message object that I get from using Zend_Mail_Imap_Storage::getMessage

please help