Hi there
Can you post his routine so we can see what is going on? He certainly doesn't need to be having milk at night at this age and it is likely a habit. Also, may I ask why you are still giving him rice cereal at this age? Is he eating regular meals with you as well?
There are two methods we use when sleep training toddlers, you can read about them here:
http://babywhispererforums.com/index.php?topic=80750.0Feeding at night for this long will be a pretty ingrained habit to break, so you can probably expect it will take some time and he will be quite upset, but really there is no need for him to be getting milk so I would advise you to try and stop as soon as possible. We'll help you figure out how.