I can't use my Google Account password to bypass the lock screen

On my CM9 / ICS 4.0 phone, if I incorrectly enter the drawn pattern five times in a row, it locks itself for 30 seconds. I can't enter any more passwords, but I can click the "Forgot my password" button and enter my Google Account password. On my rooted 4.0.3 tablet running a custom ROM, my lock screen is set with a numeric PIN. If I input it incorrectly five times or more, it locks itself and I can't enter any more passwords. I'm not offered the option to enter my Google account password to bypass this, although I have configured a Google account on the device. I want to activate the "I forgot" button in order to enter my Google Account credentials. Is it possible?