User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4 Build Identifier: version 2.0.0.4 (20070604) When writing to patrick@lumière101.com Thunderbird 2 does not punycode the domain name (IDN) before sending the message (well, it may have an option but I could not find it and it should do this properly by default). In other words, instead of sending the message to "patrick@xn--lumire101-33a.com", it sends it to the invalid address"patrick@lumire101.com" (the character > 0x7F was dropped)... BTW, after this failed a first time, I did set in about:config of Thunderbird "network.enableIDN" to "true" and added "network.IDN.whitelist.com" and set it to "true". Although, I'm not sure this had any effect. Sample returned message : Could not deliver message to the following recipient(s): Failed Recipient: patrick@lumire101.com Reason: Failed four attempts to connect to the recipients mail server. No DNS information was found for the 'lumire101.com' domain. -- The header and top 20 lines of the message follows -- Received: from dsl-205-205-142-75.cooptel.qc.ca [205.205.142.75] by skywalker.myinternetwebhost.com with SMTP; Thu, 12 Jul 2007 00:54:21 -0700 Message-ID: <4695DDFB.5040803@xcential.com> Date: Thu, 12 Jul 2007 03:53:31 -0400 From: Patrick Andries <patrick.andries@xcential.com> User-Agent: Thunderbird 2.0.0.4 (Windows/20070604) MIME-Version: 1.0 To: patrick@lumière101.com Subject: Essai Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Voilà ! Reproducible: Always Steps to Reproduce: When writing to patrick@lumière101.com Thunderbird 2 does not punycode the domain name (IDN) before sending the message (well, it may have an option but I could not find it and it should do this properly by default). In other words, instead of sending the message to "patrick@xn--lumire101-33a.com", it sends it to the invalid address"patrick@lumire101.com" (the character > 0x7F was dropped)... BTW, after this failed a first time, I did set in about:config of Thunderbird "network.enableIDN" to "true" and added "network.IDN.whitelist.com" and set it to "true". Although, I'm not sure this had any effect. Actual Results: Sample returned message : Could not deliver message to the following recipient(s): Failed Recipient: patrick@lumire101.com Reason: Failed four attempts to connect to the recipients mail server. No DNS information was found for the 'lumire101.com' domain. -- The header and top 20 lines of the message follows -- Received: from dsl-205-205-142-75.cooptel.qc.ca [205.205.142.75] by skywalker.myinternetwebhost.com with SMTP; Thu, 12 Jul 2007 00:54:21 -0700 Message-ID: <4695DDFB.5040803@xcential.com> Date: Thu, 12 Jul 2007 03:53:31 -0400 From: Patrick Andries <patrick.andries@xcential.com> User-Agent: Thunderbird 2.0.0.4 (Windows/20070604) MIME-Version: 1.0 To: patrick@lumière101.com Subject: Essai Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Voilà ! Expected Results: The message to be sent to "patrick@xn--lumire101-33a.com" !

Nope, it's not implemented yet.