For all the issues with incorrect encodings and utf-8 make sure first the environment works and you can then check if the editor in use is not the problem.
I don't know what server language you are using but do this:
Create a simple form with a text area box
Insert/Copy or type in the foreign string.
Upon form submission save the result in the database
Check with a db tool see if the string in the db is stored exactly as you typed it.
Then retrieve the text from the db and send it to the client end (browser) see if it shows as you expect.
If it's ok, then the problem is likely with the editor or its settings. Otherwise backtrack, see if it's the db encodings or some other filtering function on the server end that changes things before sending the text to the client.