Spam aping workflow

Here's an oddly evocative spam I got today (but without any attachment, rendering it moot):

This message is for the designated recipient only and may contain privileged, proprietary, or otherwise private information. If you have received it in error, please notify the sender immediately and delete the original. Any other use of the email by you is prohibited.

Hello,

Please find enclosed a record of invoice that could not be processed. We would like to ask you to assist us in resolving the noted rejection reasons

Pretty fascinating.  Clearly a delivery mechanism for some sort of PDF exploit, but de-fanged along the way.