Sendy and Slovak language encoding problem after upgrade

I ran into a problem when upgrading to from a version, that my client with campaign in Slovak language had all of his campaigns badly encoded, a lot of strange characters and question marks, I searched the forum and I was little dissatisfied with the solution, but it worked, you have to change encoding to UTF-16, it will work then.

To change encoding to Unicode UTF-16, in your installation directory /sendy/includes/config.php, add this line to end of the config file or change the variable value, if the line is already there to:

$charset = 'utf16'