Dodge Durango fuel problems?

i have a 2000 dodge durango, sometimes after i have used it for a while when i shut it off it won't start again, until it seats for a while, about 30 min, then it starts rigth up. I have no problems while it runs and it happens only a few times i can use it and start it many times during the day and nothing happens but sometimes it just doesnt start. Suspected to be a fuel problem.