diff --git a/lib/editor/popups/dlg_ins_char.php b/lib/editor/popups/dlg_ins_char.php
index f47690a17de..e3c1b58e0d9 100644
--- a/lib/editor/popups/dlg_ins_char.php
+++ b/lib/editor/popups/dlg_ins_char.php
@@ -50,7 +50,7 @@
 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html style="height: 270px;">
 <head>
-<meta http-equiv="content-type" content="text/html; <?php print_string("thischarset");?>">
+<meta http-equiv="content-type" content="text/html; charset=<?php print_string("thischarset");?>">
 <style type="text/css">
 body {
   background: ButtonFace;
diff --git a/lib/editor/popups/dlg_ins_smile.php b/lib/editor/popups/dlg_ins_smile.php
index 7f218014703..4578d956778 100644
--- a/lib/editor/popups/dlg_ins_smile.php
+++ b/lib/editor/popups/dlg_ins_smile.php
@@ -35,7 +35,7 @@
 ?>
 <html style="width: 320px; height: 350px;">
 <head>
-<meta http-equiv="content-type" content="text/html; <?php print_string("thischarset");?>" />
+<meta http-equiv="content-type" content="text/html; charset=<?php print_string("thischarset");?>" />
 <meta name=vs_targetSchema content="HTML 4.0">
 <meta name="GENERATOR" content="Microsoft Visual Studio 7.0">
 <LINK rel="stylesheet" type="text/css" href="dialog.css">
diff --git a/lib/editor/popups/insert_image.php b/lib/editor/popups/insert_image.php
index 1594ebe8d5d..e6010b7814c 100644
--- a/lib/editor/popups/insert_image.php
+++ b/lib/editor/popups/insert_image.php
@@ -10,7 +10,7 @@
 
 <head>
   <title>Insert Image</title>
-<meta http-equiv="content-type" content="text/html; <?php print_string("thischarset");?>" />
+<meta http-equiv="content-type" content="text/html; charset=<?php print_string("thischarset");?>" />
 <script type="text/javascript" src="popup.js"></script>
 
 <script type="text/javascript">
diff --git a/lib/editor/popups/insert_table.php b/lib/editor/popups/insert_table.php
index a6c7c6119ce..bdf08495f89 100644
--- a/lib/editor/popups/insert_table.php
+++ b/lib/editor/popups/insert_table.php
@@ -3,7 +3,7 @@
 ?>
 <html style="width: 398; height: 218">
 <head>
-<meta http-equiv="content-type" content="text/html; <?php print_string("thischarset");?>" />
+<meta http-equiv="content-type" content="text/html; charset=<?php print_string("thischarset");?>" />
   <title>Insert Table</title>
 <script type="text/javascript" src="popup.js"></script>
 <script type="text/javascript">
