501 Error at Adresses with Umlauts (äöü)

[gerd87]

In Germany, there are E-Mail-Addresses with Umlauts.
But if I sent a new Mail with Aqua Mail, it threw an error 501: malformed address

It must be translalte into Punnycode before it goes out.

Thank You.

[Kostya Vasilyev]

Wow. Pretty uncommon where I live.

As far as I know, punycode is not the only way to deal with this (and not always the right way either).

How common is this?

It's in the address part, correct?

The "names" can be anything, they're encoded differently.

The domain or the username part? Or both?

[gerd87]

Its new in Germany and it is becoming more common.

Only in Domain part.

for example:
username @ schön . de
must be converted to:
username @ xn--schn-7qa . de
(without Spaces)

The Conversion must be done in the Email-Client.

Thank You

[r0b0tnik]

It is the same for everywhere.
IDN with unicode is used since 2 years and getting more and more common.
The related RFC is RFC 5891. I would have put the link but this forum does not allow external links..

I also have domain name with email servers which contains Unicode and i can't send emails with aquamail if i don't use the Punycode version of my IDN. it's quite bothering.
Especially because on the sender address field there is a checker that prevent sending emails if the address seems not valid. But we should be able to send whatever we want. It's the responsibility of the smtp server to make blocking checks if you violate any of its rules but it's not the client one.

In my opinion the best solution would be  first to implement the Punycode handling as the RFC states it. And second to make any checks on email fields non-blocking (especially for address validity) or at least it should be possible to override them.

[Kostya Vasilyev]

The current RFCs are 6530-6532, and the earlier spec (RFC 58xx) was reviewed and considered unsatisfactory.

http://tools.ietf.org/html/rfc6530#section-6

There is more to it than just skipping address validation on the compose screen (and there are implications for IMAP as well).

Anyway. Yes, I'm aware of it, but don't have a solution right now.

[r0b0tnik]

I agree there is no solution at the moment for full internationalization of email addresses and more for all email fields.

But handling IDNs only is possible as web brothers do. And some other emails client do it well for addresses like : "something@ùùù[dot]tld"

For the RFCs, you're write, those about full email internationalization in 58XX are updated. But i was only pointing at domain name internationalization protocol which is actually used. And RFC5890-91 do not appear obsolete.

I do not pretend to know any better than you. But i think there might be a misunderstanding.
And it seems to be possible to just take care of IDN but not of full address internationalization.

It would be really nice to handle those IDN because Punycodes are a plague to remember.

Anyway you did quite a good job on Aquamail so thanks  ;-)

[Kostya Vasilyev]

Actually, I don't know much about it... Looked at those 5xxx RFCs, they are a mess, so I'm glad to see this:

http://tools.ietf.org/html/rfc6530#section-6

Prior to starting on the work that
led to this set of specifications, the WG concluded that the
combination of requirements and long-term implications of that
earlier model were too complex to be satisfactory and that work
should move ahead without it.

So it's just the domain part that's becoming fairly common in Germany?

<username is all ASCII> @ <domain may contain umlauts, etc>?

Do you have an example of an outgoing mail server where you've used this (with other mail apps, as you mentioned)? I'd like to check if it supports the SMTPUTF8 extension.

[Kostya Vasilyev]

Ok, to summarize: I'll take a look at this after I'm done with 1.5.1 (maybe support the SMTPUTF8 extension too, looks reasonable... Gmail has it already).

[r0b0tnik]

I'm  using a personal email server with Postfix and Dovecot.

Yes i'ts only the domain part that is used and usable. For the rest, as you said, there is no proper solution yet.
But it's not only in Germany. I use it on French domains (".fr' and ".tf"). IDNs are getting more used everywhere. Since 2011 or so language-native characters can even be used in ccTLD.
Each ccTLD have their own policies for the use of language-native characters and most of them authorize just a subset of UTF8 characters.
But I must concede that there are probably few people using email servers with those domains yet.
I don't have example of other Android email app since i'm using Aquamail but Thunderbird, EMclient (desktop clients) and Roundcube (webmail) are handling that without problem so far.

Thanks for answering and taking time to look into it.

[Kostya Vasilyev]

Thank you.

So to summarize, three tasks:

1 - non-ASCII in domain names, and strictly ASCII username parts. Punycode.

2 - full non-ASCII addresses. Will need SMTPUTF8 on the sending server.

3 - receiving (for all mail protocols)

PS - Postfix too has SMTPUTF8, but this version (2.12) isn't even in Debian "testing" or Ubuntu "vivid" yet... But it will come at some point. Thanks again.

[r0b0tnik]

Seems perfect.

I'll try using SMTPUTF8 with postfix whenever i'll have some time as it seems available on freebsd.

[Kostya Vasilyev]

Darn, it's been a long time...

I'm still interested in this, and would appreciate some help.

If anyone ever reads this... if you have an email account like that (ASCII username part @ domain with special characters), can you please send me a couple of test messages?

I just don't have any addresses / account like that.

kmansoft / at / gmail.com

kman / at / yandex.ru

Thanks!

[Kostya Vasilyev]

"ASCII email + IDN domain" done, implemented, some limited testing, but won't make it into 1.5.5.

Need help from someone with an actual address like that, for better testing.

If interested, please send a message or two to kmansoft / gmail.