We released a new development snapshot. A new stable version v4.803 should be available soon.
Changes in v4.900:
• K-9 Mail now uses a locale-specific date in the header of a quoted message
• Added support for bitcoin URIs
• Changed the way we harden SSL/TLS sockets; Blacklist a couple of weak ciphers, bring known ones in a defined order and sort unknown ciphers at the end. Also re-enable SSLv3 because it's still used a lot.
• Display proper error message when certificate couldn't be verified against global key store
• Fixed inadequate certificate validation. Proper host name validation was not being performed for certificates kept in the local keystore. If an attacker could convince a user to accept and store an attacker's certificate, then that certificate could be used for MITM attacks, giving the attacker access to all connections to all servers in all accounts in K-9.
• Make sure to return different colors for senders with different name, but the same mail address (e.g. mails sent by certain issue tracking systems).
• Fixed bug where inline images weren't displayed on KitKat
• Fixed file selection for import on KitKat
• Fixed a bug with POP3 STLS command
• Added/updated auto-configuration settings for some providers
• Updated Brazilian Portuguese, Czech, Danish, Dutch, French, Greek, Hungarian, Polish, Russian, Slovak, Spanish, and Ukrainian translations