diff --git a/cms/templates/import.html b/cms/templates/import.html
index a5c6b9f41261..27337bf235d3 100644
--- a/cms/templates/import.html
+++ b/cms/templates/import.html
@@ -72,7 +72,7 @@ <h2>${_("Course to import:")}</h2>
     add: function(e, data) {
         submitBtn.unbind('click');
         var file = data.files[0];
-        if (file.type == "application/x-gzip") {
+        if (file.name.match(/tar\.gz$/)) {
             submitBtn.click(function(e){
                 e.preventDefault();
                 submitBtn.hide();