diff --git a/modoboa/extensions/sievefilters/lib.py b/modoboa/extensions/sievefilters/lib.py
index 4d58addd5..c6ed51883 100644
--- a/modoboa/extensions/sievefilters/lib.py
+++ b/modoboa/extensions/sievefilters/lib.py
@@ -77,7 +77,7 @@ class SieveClient(object):
 
     def pushscript(self, name, content, active=False):
         if type(content) is unicode:
-            content = str(content)
+            content = content.encode("utf-8")
         if not self.msc.havespace(name, len(content)):
             error = "%s (%s)" % (_("Not enough space on server"), self.msc.errmsg)
             raise SieveClientError(error)
diff --git a/modoboa/extensions/sievefilters/static/sievefilters/js/lib.js b/modoboa/extensions/sievefilters/static/sievefilters/js/lib.js
index b705737fb..e38092166 100644
--- a/modoboa/extensions/sievefilters/static/sievefilters/js/lib.js
+++ b/modoboa/extensions/sievefilters/static/sievefilters/js/lib.js
@@ -236,6 +236,7 @@ function filtersetform_cb() {
     });
     $(".submit").one('click', function(e) {
         simple_ajax_form_post(e, {
+            formid: "newfiltersset",
             reload_on_success: false,
             error_cb: filtersetform_cb,
             success_cb: filterset_created