Glyph Lefkowitz wrote: ...
The first thing to consider is that RFC 822, the document which defines the standards and usages for email, specifically mentions this usage in section 4.4.3:
A somewhat different use may be of some help to "text message teleconferencing" groups equipped with automatic distribution services: include the address of that service in the "Reply- To" field of all messages submitted to the teleconference; then participants can "reply" to conference submissions to guarantee the correct distribution of any submission of their own.
It's not "against" the standard. It may be a quirk of the standard. Detractors, please familiarize yourselves before FUDding.
<nitpick> adding to != changing </nitpick> ;) ...
4) "It removes useful information."
If you're using the 'reply-to' header rather than your 'from' header to encode the address you want responses sent to, I know this is within the standard, but you're wasting my bandwidth and my time. I don't need to know both what machine you sent from and what machine you want me to reply to. Just put your own address in the 'from' header. (This is what most people do anyway. I don't know anyone that works otherwise.)
In addition to the valid uses posted otherwise ... Real life example: At work, I am within a corporate firewall. On my unixen, my email address is local to the machine, ie. bill@somehostname.bigcorp.com. If you reply to that, you will be wasting your time and badwidth, since you _can't_ access it from outside the firewall. Thus, I (in this example) add a reply-to that has a _useable_ email address, ie. one avaiable to you, form outside the firewall. I personally know of several hundred people who do this, and several thousand who _should_ be. And before you say it, no, not every mailer lets you set the 'from' header. The point? Now you know someone who uses it. ;^) How can this be on topic, you ask? Read on. :) I've notice a certain increase in the amount of 'sending mass email with zope' messages lately, and not many solutions. Since I don't zope on windows, one method I have used when wanting to avoid the sendmail tag (I _was_ having problems with the friggin thing not working), was to shell out and call mail (or mailx, depending on your *nix) to send each message. Problem was, when doing that, the 'from' address was 'nobody@foo.bar.com'. Since I wanted replies, I had to add the reply-to to get a response that was useful. (Hey, I din't say it was a strong effort to bring it back on topic for the list :) Perhaps those wanting to send out mass emails *cough*spam*cough* with zope, and not finding answers from within Zope and the sendlmail tag (yeah, I still look at that puppy with suspicion and a sneer :) may see this as an option -- In flying I have learned that carelessness and overconfidence are usually far more dangerous than deliberately accepted risks. -- Wilbur Wright in a letter to his father, September 1900