replace _scaytParams from editor

Hello,
in the same page I have 2 editors. The first have the language of default it_IT the second english

For the second I must replace the _scaytParams...

I tried this 3 version (see red code), where is the problem????? THANKS
$CKEditor->config['_scaytParams'] = array("sLang" => 'en_US');
$CKEditor->config['_scaytParams'] = 'en_US';
$CKEditor->config['scayt_sLang'] = 'en_US');

<?php
 include("../editor/ckeditor.php");
 $CKEditor = new CKEditor();
$CKEditor->returnOutput = true;
$CKEditor->basePath = '../editor/';
$CKEditor->config['_scaytParams'] = array("sLang" => 'en_US');
 $CKEditor->config['width'] = 650;
$CKEditor->config['height'] = 150;
 $CKEditor->config['toolbar'] = 'testi';
$CKEditor->textareaAttributes = array("cols" => 78, "rows" => 30);
$initialValue = $descrizione_en;
$code = $CKEditor->editor("descrizione_en", $initialValue);
echo $code;
 ?>