Support for internationalized email addresses
Aug 21, 2023
An internationalized email address is an address that contains characters of national (non-Latin) alphabets, such as:
- Cyrillic (.рф domain)
- Chinese (Traditional) (.中國 domain)
- Chinese (Simplified) (.中国 domain)
The program processes messages with internationalized email addresses according to the same rules that are applied to all other messages. In addition, internationalized addresses can be used for sending notifications and reports.
The comparison of the local and domain portion of internationalized addresses against the addresses and regular expressions specified in the processing rules is not case sensitive.
When a message with an internationalized address is moved to the message queue or to Backup, the program saves the values of the From and To headers in the following formats:
The internationalized address is saved without changes.
Before the address is saved, the following conversions occur:
- Conversion of the domain portion of the address from Punycode to Unicode
- Conversion of the address to canonical form in which the case of characters is ignored (Unicode Case Folding)
- Conversion of characters with the same font to the same binary representation (Unicode Normalization)
The values of the Subject and ID headers are saved only in normalized format.
When calculating statistics in a report, the program uses the normalized form of addresses of the mail sender and recipient. In addition, internationalized addresses written in uppercase and lowercase characters and/or using Punycode are considered to be the same address.