Does Photoshop CS4 require you to manually create alpha channels to save clear images?

I use 7.0 and it automatically saves images as you make them transparent or opaque. I have never had to create an alpha channel because it already does it. But when I tried demos of the newer versions of photoshop, instead of saving the TGA image as clear or opaque, it just makes the checkered areas solid white.





Does anyone know why? Did they remove this feature from the newer versions?Does Photoshop CS4 require you to manually create alpha channels to save clear images?
I'm not sure about TGA's but you could save it as a gif or png.


File %26gt; Save for Web (make sure transparency is checked)