I once substituted spelt flour for regular flour in one of my sponge cakes - it didn't work - it was supposed to be a very airy and fluffy cake but because of the substitution it became a dense and hard cake. Depending on the recipe flour substitutions don't always work unfortunately. You have to get a recipe which specifically mentions the different use of flours...
Swsha - although I don't know of any specific recipes to substitute for cake flour I do know of a really good gluten free blog that could get you going in the right direction: http://myglutenfreecookbook.blogspot.com/
She also has a ton of gluten free blogs in her blogroll. Check it out, maybe you can find your answer there!
I am wondering if one can substitute spelt flour for cake flour in baking cakes. I know that cake flour has less gluttons than all-purpose and spelt does too, so I was wondering if it would react the same. If not, is there a way to compensate and still use it?
I have a family member who can eat spelt but not regular wheat and many other wheat flours.