diff --git a/modoboa/admin/templatetags/admin_tags.py b/modoboa/admin/templatetags/admin_tags.py
index e7abbd24a..6a202fb6d 100644
--- a/modoboa/admin/templatetags/admin_tags.py
+++ b/modoboa/admin/templatetags/admin_tags.py
@@ -5,6 +5,7 @@ Admin extension tags.
 from django import template
 from django.core.urlresolvers import reverse
 from django.template.loader import render_to_string
+from django.utils.safestring import mark_safe
 from django.utils.translation import ugettext as _, ugettext_lazy
 
 from modoboa.lib import events
@@ -192,7 +193,7 @@ def identity_actions(user, ident):
     return render_actions(actions)
 
 
-@register.assignment_tag
+@register.simple_tag
 def check_identity_status(identity):
     """Check if identity is enabled or not."""
     if identity.__class__.__name__ == "User":
@@ -232,7 +233,7 @@ def domain_aliases(domain):
     res = ''
     for alias in domain.aliases.all():
         res += '%s<br/>' % alias.name
-    return res
+    return mark_safe(res)
 
 
 @register.simple_tag
@@ -283,4 +284,4 @@ def get_extra_admin_content(user, target, currentpage):
     res = events.raiseQueryEvent(
         "ExtraAdminContent", user, target, currentpage
     )
-    return "".join(res)
+    return mark_safe("".join(res))
diff --git a/modoboa/core/templatetags/core_tags.py b/modoboa/core/templatetags/core_tags.py
index eb1f8cd1b..fa836c41c 100644
--- a/modoboa/core/templatetags/core_tags.py
+++ b/modoboa/core/templatetags/core_tags.py
@@ -7,6 +7,7 @@ from django.contrib.sessions.models import Session
 from django.core.urlresolvers import reverse
 from django.template.loader import render_to_string
 from django.utils import timezone
+from django.utils.safestring import mark_safe
 from django.utils.translation import ugettext as _
 
 from modoboa.lib import events
@@ -149,11 +150,12 @@ def visirule(field):
             field.html_name not in field.form.visirules:
         return ""
     rule = field.form.visirules[field.html_name]
-    return " data-visibility-field='%s' data-visibility-value='%s' " \
-        % (rule["field"], rule["value"])
+    return mark_safe(
+        " data-visibility-field='{}' data-visibility-value='{}' "
+        .format(rule["field"], rule["value"]))
 
 
-@register.assignment_tag
+@register.simple_tag
 def get_version():
     import pkg_resources
     return pkg_resources.get_distribution("modoboa").version
@@ -234,10 +236,10 @@ def display_messages(msgs):
     else:
         timeout = "undefined"
 
-    return """
+    return mark_safe("""
 <script type="text/javascript">
     $(document).ready(function() {
         $('body').notify('%s', '%s', %s);
     });
 </script>
-""" % (level, text, timeout)
+""" % (level, text, timeout))