Text broken by accented chars

Hello ckeditor community !

I just added ckeditor to my future website and it works perfectly, almost.
I'm french, and many accented words like "é" or "è" or "ê" are used in my language. Ckeditor let me write these but break the final message put in the post request :
For example : " Merci pour votre réponse !"
Become : " Merci pour votre r"

my build-config.js: 
var CKBUILDER_CONFIG = {
    skin: 'bootstrapck',
    preset: 'basic',
    ignore: [
        'dev',
        '.gitignore',
        '.gitattributes',
        'README.md',
        '.mailmap'
    ],
    plugins : {
        'about' : 1,
        'basicstyles' : 1,
        'clipboard' : 1,
        'enterkey' : 1,
        'entities' : 1,
        'floatingspace' : 1,
        'indentlist' : 1,
        'justify' : 1,
        'link' : 1,
        'list' : 1,
        'toolbar' : 1,
        'undo' : 1,
        'wysiwygarea' : 1
    },
    languages : {
        'en' : 1,
        'fr' : 1
    }
};

my config.js:

CKEDITOR.editorConfig = function( config ) {
    // Define changes to default configuration here.
    // For complete reference see:
    // http://docs.ckeditor.com/#!/api/CKEDITOR.config

    // The toolbar groups arrangement, optimized for a single toolbar row.
    config.toolbarGroups = [
        { name: 'document',       groups: [ 'mode', 'document', 'doctools' ] },
        { name: 'clipboard',   groups: [ 'clipboard', 'undo' ] },
        { name: 'editing',     groups: [ 'find', 'selection', 'spellchecker' ] },
        { name: 'forms' },
        { name: 'basicstyles', groups: [ 'basicstyles', 'cleanup' ] },
        { name: 'paragraph',   groups: [ 'list', 'indent', 'blocks', 'align', 'bidi' ] },
        { name: 'links' },
        { name: 'insert' },
        { name: 'styles' },
        { name: 'colors' },
        { name: 'tools' },
        { name: 'others' },
        { name: 'about' }
    ];

    // The default plugins included in the basic setup define some buttons that
    // are not needed in a basic editor. They are removed here.
    config.removeButtons = /*'Cut,Copy,Paste,Undo,Redo,Anchor,Underline,Strike,Subscript,Superscript'*/ 'Anchor';

    // Dialog windows are also simplified.
    config.removeDialogTabs = 'link:advanced';
};

I think it's an error of my own, maybe a bad configuration in js files, or a missing plugin, because this forum message is proving that these chars are accepted by ckeditor.
Thanks in advance for your help.

Leenzur.