How to solve the security problem of Siri in iPhone 4S?

iphone-4s-siri

Siri, the most prominent feature in iPhone 4S, now has a security hole. Basically, screen lock will not prevent Siri from doing a lot of things: from sending messages to initialize a phone call on your list. Actually, except  launching apps, Siri can do almost everything when screen lock is on.This is potentially a security ...