Transparency & Max

Look at the picture. The gates on the right are OK. The gates on the left you can see through all of them. In Max, I used a single-sided transparent (with an Alpha channel, tga), and on the rest of the glass sections I have used a double-sided texture. Sometimes this happens, sometimes not...What can I do to avoid this? Do I have to make the transparent parts double-textured as well, or must force the material to be two-sided?Arrgghh what a mess this is...