diff --git a/lib/editor/htmlarea.php b/lib/editor/htmlarea.php
index 7225beb0b2e..aa882feee0d 100644
--- a/lib/editor/htmlarea.php
+++ b/lib/editor/htmlarea.php
@@ -8,7 +8,8 @@
         ob_start("ob_gzhandler");
     }
 
-    header("Content-type: application/x-javascript");  // Correct MIME type
+    $charset = get_string('thischarset');
+    header("Content-type: application/x-javascript; charset: $charset");  // Correct MIME type
     header("Last-Modified: " . gmdate("D, d M Y H:i:s", $lastmodified) . " GMT");
     header("Expires: " . gmdate("D, d M Y H:i:s", time() + $lifetime) . " GMT");
     header("Cache-control: max_age = $lifetime");
@@ -678,7 +679,7 @@ HTMLArea.prototype.generate = function () {
         html += '"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">\n';
         html += "<html>\n";
         html += "<head>\n";
-        html += '<meta http-equiv="content-type" content="text/html; charset=<?php print_string("thischarset");?>" />\n';
+        html += '<meta http-equiv="content-type" content="text/html; charset=<?php echo $charset; ?>" />\n';
         if (editor.config.baseURL)
             html += '<base href="' + editor.config.baseURL + '" />';
         html += '<style type="text/css">\n' + editor.config.pageStyle + "td { border: 1px dotted gray; }</style>\n";
diff --git a/lib/editor/lang/en.php b/lib/editor/lang/en.php
index eb83a0735f6..8172a375317 100644
--- a/lib/editor/lang/en.php
+++ b/lib/editor/lang/en.php
@@ -7,7 +7,8 @@
         ob_start("ob_gzhandler");
     }
 
-    header("Content-type: application/x-javascript");  // Correct MIME type
+    $charset = get_string('thischarset');
+    header("Content-type: application/x-javascript; charset: $charset");  // Correct MIME type
     header("Last-Modified: " . gmdate("D, d M Y H:i:s", $lastmodified) . " GMT");
     header("Expires: " . gmdate("D, d M Y H:i:s", time() + $lifetime) . " GMT");
     // See Bug #2387
diff --git a/lib/editor/popups/fullscreen.php b/lib/editor/popups/fullscreen.php
index 46076314227..128aeba430f 100644
--- a/lib/editor/popups/fullscreen.php
+++ b/lib/editor/popups/fullscreen.php
@@ -15,8 +15,8 @@
 html, body {    margin: 0px; border: 0px; background-color: buttonface; } </style>
 
 
-<script type="text/javascript" src="../htmlarea.php?id=<?php p($id); ?>" charset="<?php print_string('thischarset'); ?>"></script>
-<script type="text/javascript" src="../lang/en.php" charset="<?php print_string('thischarset'); ?>"></script>
+<script type="text/javascript" src="../htmlarea.php?id=<?php p($id); ?>"></script>
+<script type="text/javascript" src="../lang/en.php"></script>
 <script type="text/javascript" src="../dialog.js" charset="<?php print_string('thischarset'); ?>"></script>
 <script type="text/javascript" src="../plugins/TableOperations/table-operations.js" charset="<?php print_string('thischarset'); ?>"></script>
 <script type="text/javascript" src="../plugins/TableOperations/lang/en.js" charset="<?php print_string('thischarset'); ?>"></script>