Guild Navigator said:she also understood that the doorknob was the key to geting inside and out so if you weren't quick to let her out she'd start trying to turn the knob herself. she never was able to get a good grip on it do to her lack of thumbs though.
A friend of mine had a cat that used to jump up and hit the doorbell when it wanted to get in. It also used to hit the snooze on the alarm clock the instant it went off, resulting in a lot of late for work incidents until my friends father woke up early one day and saw who the culprit was.