8300 auto keyboard lock

I've had blackberry's for years and my wife has an 8300. How do I get it to lock the keyboard after +-30 secs. She drops it in her purse and it will eventually start dialing someone. I've checked the manuals but nothing specific. Does the 8300 have this option? I'm to the point of trashing the BB and getting her a flip phone. Can't believe blackberry is this complicated for something that should be so simple. I've had $40 phones that done this auto and then u push 2 buttons to unlock! simple!! Any thoughts or ideas would be appreciated. please keep instructions simple for a newbie
DD

I don't see a timed lock in the manual, but if its there it will probably be under Options/Security/Password. You would also need to set Allow Dial from Lock Screen = No.

The easiest method is simply to push the Mute key - this should put the phone to standby but it does need a little self control. The better case designs also have a sleeper magnet which automatically puts the phone to standby when it goes into the case - and it protects the phone from all the debris which accumulates in a purse. Something like https://forums.crackberry.com/e?link...token=p31-1Vn3 might be a good choice
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