User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8) Gecko/20051111 Firefox/1.5 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8) Gecko/20051111 Firefox/1.5 While browsing through my Thunderbird address book I noticed that it tends to add the same email address multiple times. For example, it would add the following: - Rainer Koschnick <rainer.koschnick@xxx.com> - Rainer Koschnick <Rainer.Koschnick@xxx.com> - Rainer Koschnick <rainer.Koschnick@Xxx.com> - Rainer Koschnick <Rainer.Koschnick@Xxx.com> So I think it should do a case-insensitive search before it decides to add the address to the address book. Reproducible: Always Steps to Reproduce: 1. Reply to an email 2. Outgoing email address will be added to address book 3. Reply to an email with same sender, but different case of letters 4. Outgoing email address will be added to address book Actual Results: Address book contains email address 3-4 times Expected Results: Address book contains email address once Do the check for an existing email address case-insensitively

Actually, email-address are case-sensitive before the '@' sign (john.doe@example.com isn't the same as JOHN.DOE@example.com or John.Doe@example.com), see RFC822, para 6. But in reality that doesn't happen, and lots of mail-applications (client, server, MTA, ..) will happily translate from uppercase to lowercase and back. If the address collection would use it, it would be a big advantage. *** This bug has been marked as a duplicate of 129393 ***

verified dup.

To the best of my knowledge this bug still exists in the main code. To get it fixed please go to bug 129393 and click the vote button to raise its level of importance.