Either your thermostat is faulty and needs to be replaced or something else is simply broken. See if it's still under warranty, if so get it fixed that way. If not call a repair man to come fix it. I got this from "Fridge Doctor" at http://answers.yahoo.com/question/index?qid=20080311160215AAaCBHa Don't know if it will help or not. See if you think it's worth a shot. "There is one of three reasons why your fridge section is freezing food. You didnt mention whether you had a side by side or freezer on top or bottom model, so the following checks may not apply to your unit. One reason food might be freezing is your cold control has failed, and will not turn the unit off when the physical temps are correct. When this occurrs food normally freezes throughout fridge section, top, bottom, middle, front and back. BOTH controls, though you may only have one, should be at the middle setting. Adjust your controls, place a plastic cup of water at the top, the middle, and bottom shelf of your fridge. Check all three AFTER 24 hours. if all three are ice, you COULD have a bad cold control. It is possible you might also have a door damper that is stuck open. A door damper is a swinging or sliding door that opens / closes either when temp control settings are adjusted, or on some fridges, when either door is opened, the damper closes. Please note, door dampers are USUALLY only present on side by side refrigerators. They can have a motor, or thermostat open the door automatically,which can break, and others will simply have a lever of some sort, which usually wont. If after 24 hours, only the middle and bottom cups are ice, your evaporator fan motor, in the freezer, is likely not operating. Not knowing the BRAND you own, it could be the motor itself, a thermostat located on the evaporator, your defrost heater, or a main computer control board that controls the fan motor. Sorry I cant be as specific as id like, but i had to cover all possible bases."

Try using the top shelf for items that you want to protect from freezing and put the less cold sensitive items near the bottom.

I would try turning the freezer down also, as long as that food stays frozen it will defiantly lower the temp a little on the other side. May not fix the problem but worth a try.

Most modern side by sides have vents near the top and bottom, and usually they can be adjusted. Try adjusting those down.