Just as an FYI, I subscribed to a newsletter with a username+something@gmail.com address, and when I later tried to unsubscribe, it couldn’t find me. The listserv software was apparently converting the “+” to a space in my unsubscribe message. I finally had to set up a filter to automatically delete those messages.

I never thought about that, but that could pose a lot of problems!

Just as an FYI, I subscribed to a newsletter with a username+something@gmail.com address, and when I later tried to unsubscribe, it couldn’t find me. The listserv software was apparently converting the “+” to a space in my unsubscribe message. I finally had to set up a filter to automatically delete those messages.

Try username%2Bsomething@gmail.com when you try to unsubscribe. (%2B is the URI encoded version of + )

I have tested it just before, it seems like that it is invalid if a gmail address which originally includes a dot.

Opps, sorry, I make a mistake.
It indeed works for me.

I am wondering if this is valid the other way around, that is, is a gmail address which originally includes a dot (name1.name2 AT gmail.com) recognized under the form name1name2 AT gmail.com (without the dot), or n.ame1name2 and so on.

Of course I could test, my point is rather theoretical.

I have tested it just before, it seems like that it is invalid if a gmail address which originally includes a dot.

Of course I could test, my point is rather theoretical.