Auto Responses not working

[BitSprocket]

All,

I know there must be some other folks that have run into this issue but I could not find the solution via search so here goes:

I can configure the auto responses and see them in the history for a given ticket and the syslog shows that they've been sent but they are never received by the customer. In contrast, any replies I make to tickets via the Reply drop down work just fine. I've checked that the auto response is valid, assigned it to the proper queue (for now everything gets dumped into Raw) and that the Auto Responses <-> Queue shows that for Raw the New Ticket (of type auto reply) is selected.

I'm not finding any errors anywhere in any logs that would clue me in to why these auto responses fail while manual ones work just fine.

Thoughts?