Add some note about gmail being crap (again)

doc/source/misc/ssl.rst

@@ -38,6 +38,11 @@ case, you should notify the administrator that his XMPP server configuration
 is probably not great), or if you want to be even more restrictive (only allowing
 256 bits of security *and* forward secrecy, for example).
 
+For example, gmail.com (and subsequent XMPP services) only support RC4-MD5 and RC4-SHA,
+so you will want to set the option to ``RC4`` (or the default with ``:RC4`` appended,
+just in case they upgrade their service, though that is very unlikely). Please consider
+moving to a better XMPP service provider.
+
 Certificate validation
 ~~~~~~~~~~~~~~~~~~~~~~
 

doc/source/misc/troubleshooting.rst

@@ -6,7 +6,7 @@ I cannot connect.
 
 1. Check that you are still connected to the internet.
 2. Double-check your credentials.
-3. Check the :ref:`security settings <security settings>`, maybe your server does not support encryption, or only with weak parameters.
+3. Check the :ref:`security settings <security settings>`, maybe your server does not support encryption, or only with weak parameters (like gmail).
 4. Maybe your DNS are wrong, try setting the :term:`custom_host` option with the server IP.
 5. Overzealous firewall?
 6. Running poezio with -d file.txt (debug mode) might reveal your issues.