Planar objects with opacity maps matteing out the fume smoke

[Suspensa]

I had no luck finding the right settings to make this go away so here is a link to a stripped down version of the file in question (Can't release the full file as you probably understand).

http://user.sancsoft.net/Steam01.zip

In the zip is included the maps used for opacity with the objects oriented the same as in the scene i'm having trouble with. There is also a folder with 2 frames of the fume sim to show what is happening. The total file size is 15 mb. Any help would be greatly appreciated.

thanks,

Spencer