diff --git a/actions/newnotice.php b/actions/newnotice.php
index b576e13266..056b45b8aa 100644
--- a/actions/newnotice.php
+++ b/actions/newnotice.php
@@ -43,7 +43,7 @@ class NewnoticeAction extends Action {
 		if (!$content) {
 			$this->show_form(_('No content!'));
 			return;
-		} else if (strlen($content) > 140) {
+		} else if (mb_strlen($content) > 140) {
 			$this->show_form(_('That\'s too long. Max notice size is 140 chars.'));
 			return;
 		}