Pidgin-sipe failed to authenticate to server while connecting to Office 365

For the last few days, an increasing number of Pidgin-sipe users have been rejected while trying to connect to their Office 365 accounts.
According to the SIPE developers, Lync servers (Office 365) have started rejecting the RC4 stream cipher. Even though it breaks the SIPE plugin, this could be seen as an improvement as Microsoft has recommended to retire RC4 as used in their TLS implementations for years.

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