K.H.
If you can get on the website widesmiles.org, they are supposed to have some great info on issues with cleft palates. I read that it is important to start out slow and have a lot of patience. One site that I looked at recommended starting with foods very liquidy so that they go down easier and then gradually start to thicken them. This is so they go down easier and don't come out of the nose as easy. One site I looked at said that it will take your son a little longer to get the hang of it but he will. If you go on yahoo and type in "starting solids with a cleft palate" you should get a lot of info. I hope this helps
K.