akonadiserver forces the socket filename from the hostname. If the hostname contains probably any non-ASCII characters, the socket cannot be found.

The Options="UNIX_SOCKET=" in ~/.config/akonadi/akonadiserverrc gets overwritten by the server start command parameters, so I couldn't manually change the socket name.

After failing, the config gets changed to this:
Options="UNIX_SOCKET=/home/jaakko/.local/share/akonadi/socket-j\xe4\xe4karhu/mysql.socket"


Reproducible: Always

Steps to Reproduce:
1. # hostname jääkarhu
2. # /etc/init.d/dbus restart
3. startx
4. akonadictl start
Actual Results:  
...
mysql.user                                         OK
Unable to listen on Unix socket "/home/jaakko/.local/share/akonadi/socket-jääkarhu/akonadiserver.socket"
...
ProcessControl: Application 'akonadiserver' returned with exit code 255 (Unknown error)
"akonadiserver" crashed too often and will not be restarted! 


As a result, there are four mysqld processed running with following parameters:
/usr/sbin/mysqld --defaults-file=/home/jaakko/.local/share/akonadi/mysql.conf --datadir=/home/jaakko/.local/share/akonadi/db_data/ --socket=/home/jaakko/.local/share/akonadi/socket-jääkarhu/mysql.socket


Expected Results:  
akonadiserver starting ok.

Works fine after I change the hostname to something with only ASCII characters, and restart the dbus.