Nokia 6300 Security Keyguard

I have access to a Nokia 6300 on an O2 pay as you go contract. The phone has a four digit security keyguard on it. I can keep retrying the security keyguard without it timing out but that'll take ages and I suspect the code is being changed once a week.

Is there a way to find out the keyguard pin or view it with some sort of software? I'd like access to the phone without the user knowing I have.

Many thanks in advance for any and all help on the matter.