I think I remember reading somewhere that eating tomatoes can help with this problem
Are they cracks or just dry skin ? Try using a bit of vaseline each night
It's called Angular Chelitis and as pastafreak mentions can be caused by dietary inadequacy. The body can't store vitamin B2 which can cause this so it's important to have a regular dietary source. It can also be caused by a lack of B12, Anemia and is also found in people who have liver disease and alcoholics. Perhaps if you Google Angular Chelitis it will give you a bit more info on ways to treat it.
moonshadow, i think you have hit the nail on the head,
as throughout her life she has suffered from anaemia,
thanks very much for your most adequate answer, and
to all those who replied. Bye for meow
Does she use steroid inhalers? If I don't clean my teeth/mouth immediately after using mine I get oral thrush which affects the corners of my mouth. I use a good lip balm, along with a mouth wash to help it on it's way.