diff --git a/lib/moodlelib.php b/lib/moodlelib.php
index 0132736..804d1e8 100644
--- a/lib/moodlelib.php
+++ b/lib/moodlelib.php
@@ -7194,7 +7194,7 @@ function check_php_version($version='5.2.4') {
 
       case 'MSIE':   /// Internet Explorer
 
-          if (strpos($agent, 'Opera')) {     // Reject Opera
+          if (strpos($agent, 'Opera') or strpos($agent, 'chromeframe')) {     // Reject Opera & ChromeFrame
               return false;
           }
           $string = explode(';', $agent);
@@ -7233,6 +7233,8 @@ function check_php_version($version='5.2.4') {
               if (version_compare($match[1], $version) >= 0) {
                   return true;
               }
+          } else if (strpos($agent, 'chromeframe')) {
+              return true;
           }
 
           break;