new rabbit woes

Question
we have just adopted a 4 year old male dutch rabbit. the previous owner had allergy problems in the household.
we have had him for a week now, at first he was willing to come out of his cage if left alone for a few minutes, he'd explore his surroundings and jump up in our laps for a snuggle. we'd get his cage cleaned out in this time, and put in fresh water and pellets.
i did notice that he'd marked his territory, the first few times he was out, but after placing a litter box in his favourite corner, he'd go to it when needed. as far as i can tell, there are no litter training issues.
now in the last day or two, he doesn't want to come out of his cage. we've had a few other people in the basement when he was out lately, but he's been pretty social, so we didn't expect there to be a problem.
can you suggest any reasons why he may not want to come out? i don't want to take him out, since i've read that they need to feel that their cage is a secure place.
when i put my hand in the cage to pet him, he always give me a sniff and seems happy to be petted, but can't be coaxed out with lettuce or carrots.
any other ideas on how to make this transition period go well, would be appreciated. thanks, terri.

Answer
Is he maybe ill?  Is there something in the area that scares him (loud noises, smoking)?  

Does he sit huddled up in one corner?  If so, then he may be ill.  If he is hopping around and eating and drinking normally, it may be situational.

If he is ill, he should see a vet, but if he isn't ill, you may need to find why he isn't coming out, which would mean looking for things that he is sensitive to and moving them.  Rabbits react to strong smells, loud noises, and other animals such as cats or dogs.  

I hope this helps you out, without knowing what he is thinking it is kind of hard to tell!

Kim