User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.7.5) Gecko/20041124 Firefox/1.0 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; zh-CN; rv:1.7.5) Gecko/20041124 Firefox/1.0 My mail's subject is '=?gb2312?B?xPq1xMr919bWpMrp0tG+rde8sbi6w8HL==?=', but Thunderbird just display '=?gb2312?B?xPq1xMr919bWpMrp0tG+rde8sbi6w8HL==?=' in message window. To: zhanghs@gmail.com From: zhanghs@gmail.com Subject: =?GB2312?B?xPq1xMr919bWpMrp0tG+rde8sbi6w8HL==?= MIME-Version: 1.0 Content-Type: text/plain; charset=gb2312 Content-Transfer-Encoding: 8bit Reproducible: Always

What is exact version of your Thunderbird? (Bugzilla nor Browser can not know your mailer's version. You have to write it by yourself.) Is message body in charset=gb2312 displayed as expected? Is this Thunderbird only problem or problem on both Thunderbird and Mail&News? (For MS Win, ZIP build is available. Module name is mozilla-i586-pc-msvc.zip.) (This can very easily be tested - usable by only unzip. ) GB_2312-80 is listed in both RFC 1345 ( http://www.faqs.org/rfcs/rfc1345.html ) and IETF IANA ( http://www.iana.org/assignments/character-sets ), but GB2312 is listed in IANA only. Is changing "gb2312" in subject header to "GB2312" or "GB_2312-80" a workaround? (1) Create a mail folder(say "TEST") (2) Copy the mail to "TEST" folder twise, then compact folder(make sure only two mails) (3) Shutdown Thunderbird (4) Edit "TEST" file(not "TEST.msf") in mail directry, then change "gb2312" to "GB2312" and "gb2312" to "GB_2312-80" (5) Delete "TEST.msf" file (6) Restart Thunderbird

The subject is invalidly encoded -- it's declared in Base64, which requires that the encoded string be an even multiple of 4 bytes; this string is 34 bytes, the two '=' signs at the end (before the terminating "?=") are superfluous. The dupe has a discussion on whether Mozilla should or should not allow superfluous padding. *** This bug has been marked as a duplicate of 227290 ***