Freezers and fridges work by using a heat pump. Heat from the inside is moved to the outside (and it takes work/heat/energy to move the heat). So more heat is generated than is removed from inside.
It isn't necessarily bad for your freezer to be hot on the outside - it just means that heat is being pumped from inside. However, constant high temperatures may mean there is a fault. In particular - if the door is not closing properly or there is a poor seal around the door then the pump may be operating for extended periods of time (and you are likely to get frost build up internally).
You should also ensure sufficient ventilation around your freezer to ensure that heat is carried away (The higher the temperature around your freezer, the harder the pump has to work to remove a given portion of heat).
Mark
April 2005