Do you mean you know the password and you want to stop putting it in? If you don't know the password, all you can do is get it wrong until the device resets. If you just want to stop it asking for a password, go to Settings>Security and set Password to disabled.
Did you check if you are able to change the setting under Options->Security on your Blackberry? If you can not change the setting then your BB got a security policy applied. To remove the policy you would need to connect your BB to a BES and assign an empty policy.
And it hasn't occured to you that someone might be looking for it?
It's probably been blocked by the carrier by now if it's been reported missing. It won't be any use to you if you had the password. But at the end of the day, the password can't be cracked.
Blackberry 7730
