Auto MX Email Client configuration, the right way?

[Davide Marchi]

> Now I've seen the new RFC 6186 specification
> (https://tools.ietf.org/html/rfc6186) that describe a "DNS way" to
> achieve the same goal.
> 
> [..]
> again:
>     [..]
>     When a user identifier is required, MUAs MUST first
>     use the full email address provided by the user, and if that 
> results
>     in an authentication failure, SHOULD fall back to using the "local-
>     part" extracted from the email address.  This is in line with the
>     guidance outlined in Section 5.  If both these user identifiers
>     result in authentication failure, the MUA SHOULD prompt the user 
> for
>     a valid identifier.
>     [..]
> 
> here I have the biggest doubt, in fact Thunderbird often uses only the
> username and not the whole email address, both for incoming and 
> outgoing
> server...
> Is any of you using this second way? And possibly, do you kniw if it
> works with different clients (desktop and mobile)?

I've made some tests and this solution seems very serviceable, for the 
only exception for the user name on Thunderbird.
Unlike what is stated in this RFC, Thunderbird "takes" only the name and 
not the entire email address as the username.
Anyone knows if is it possible to communicate the username type via RFC?

Many thanks again!


Davide