According to latest reports, the new Siri on iPhone 4S, unfortunately, allows anyone to use the phone to send e-mails, text messages and make calls even though the device is password-protected.

The problem has been reported by several users who have complained that their friends were able to make calls or send messages and mails from their iPhone 4Ss without even knowing the password.

According to Sophos, there is a procedure to get rid of this problem temporarily. The user just needs to switch Siri off in the passcode lock settings, which is found in General and then Settings. This will let the user use the voice assistant once the device is unlocked by removing the passcode.

iPhone 4S owners were not aware of this fact till people started complaining about how others can make use of their devices without the owner's consent. Switching Siri off from settings, however, has put an end to such problems, but the main point of concern is that this procedure is just a temporary fix and leaves the device vulnerable if the user forgets to switch Siri off.

I borrowed a passcode-locked iPhone 4S from a colleague here at Sophos and, with his permission, was able to write an e-mail, and send a text message. If I had wanted to, I could have meddled with his calendar appointments too, wrote Graham Cluley of Sophos. All without having to enter the passcode. I'm sure you can imagine some of the ways this could potentially be abused.

Siri also is showing problems of misunderstanding what the user actually wants to say, according to a Sophos report.

Siri, which was founded in December 2010 by Dag Kittlaus, Adam Cheyer and Tom Gruber, along with Norman Winarsky from SRI International's venture group, makes use of natural language processing to answer questions, make recommendations, and perform actions by assigning requests to an expanding set of Web services. The software claims to adapt to the user's individual preferences over time, personalizing results and accomplishing tasks.