H.V.
find a way to be able to lay down with him in his room (if you really prefer him to sleep in his room). and then get up to leave the room after he falls to sleep.
with all three of our boys I have laid down with them to help them get to sleep and then get up when they have fallen asleep. not every time, but sometimes
our boys are 13, 6 and 18 mths old.
oh, I just thought of this site:
http://www.freewebs.com/sidecarcrib/ maybe if you need to try this, it may also help you all to get a good night's sleep. this is how we have our crib and bed set up. it's not my site...but we have used this set up for our 2 youngest children. now the 6 year old is in his own room...and has been since about age 2 or 2 1/2. I can't remember when we moved him to his own room. he shares a room with his older brother.