valid_email() to always return boolean
diff --git a/system/libraries/Form_validation.php b/system/libraries/Form_validation.php
index f3087f8..3536241 100644
--- a/system/libraries/Form_validation.php
+++ b/system/libraries/Form_validation.php
@@ -1076,7 +1076,7 @@
 	 */
 	public function valid_email($str)
 	{
-		return filter_var($str, FILTER_VALIDATE_EMAIL);
+		return (bool) filter_var($str, FILTER_VALIDATE_EMAIL);
 	}
 
 	// --------------------------------------------------------------------