diff --git a/classes/Mail.php b/classes/Mail.php
index a23422301..c840225ec 100644
--- a/classes/Mail.php
+++ b/classes/Mail.php
@@ -83,7 +83,7 @@ class MailCore
 		}
 
 		/* Construct multiple recipients list if needed */
-		if (is_array($to))
+		if (is_array($to) and isset($to))
 		{
 			$to_list = new Swift_RecipientList();
 			foreach ($to AS $key => $addr)
diff --git a/classes/Validate.php b/classes/Validate.php
index 6c7bbcdca..85ece9cfa 100644
--- a/classes/Validate.php
+++ b/classes/Validate.php
@@ -45,7 +45,7 @@ class ValidateCore
 	*/
 	public static function isEmail($email)
     {
-    	return empty($email) OR preg_match('/^[a-z0-9!#$%&\'*+\/=?^`{}|~_-]+[.a-z0-9!#$%&\'*+\/=?^`{}|~_-]*@[a-z0-9]+[._a-z0-9-]*\.[a-z0-9]+$/ui', $email);
+    	return !empty($email) AND preg_match('/^[a-z0-9!#$%&\'*+\/=?^`{}|~_-]+[.a-z0-9!#$%&\'*+\/=?^`{}|~_-]*@[a-z0-9]+[._a-z0-9-]*\.[a-z0-9]+$/ui', $email);
     }
 
     /**