Correct format of an Return-Path header

Question

My application uses sendmail to send outbound email. I set the 'From:' address using the following format:

Fred Dibnah <[email protected]>

I'm also setting the Reply-To and Return-Path headers using the exact same format.

This seems to work in the vast majority of cases but I have seen at least one instance in which this fails, namely when the name part of the above string contains a period (full stop):

Fred Dibnah, Inc. <[email protected]>

This fails deep inside the TMail code (I'm using Ruby) but it seems like a perfectly valid thing to do.

My question is, should I actually be setting the Return-Path and Reply-To headers using only the email address as opposed to the above Name + Email format? E.g.

[email protected]

Thanks.