Google's ongoing elimination of the antediluvian SSLv3 and RC4 protocols is taking another step on June 16.
From that date, Gmail's IMAP and POP services will join its SMTP services in rejecting connections using those protocols.
Recognising, perhaps, that not everybody's been paying attention, Mountain View is giving users and sysadmins time to adjust. It may take “longer than 30 days for users to be fully restricted from connecting” using clients that still run those protocols, the company's announcement states.
However, most clients already support more modern TLS versions.
Beyond the deprecation date, sysadmins will start to see errors if they try running SSLv3 or RC4 in connection, and app developers are likewise warned they need to push out upgrades.
And as a cipher, RC4 has been a dead duck for years.
So if your favourite mail app tells you “upgrade now”, you might want to ask why they've taken so long. ®