Transparent shader & Particles issue

Hello,

I'm experiencing this odd effect when displaying a particle effect near an object with a transparent shader.

The images attached show when a "fire" effect is turned on "over top of" a plane with a transparent material.

Notice that the fire particles seem to go under the ground shadow plane and has a different color. I'm using the stock transparent/diffuse shader for the ground shadow plane.

Any ideas how to stop this or what might be going on?

Thanks!...

Transparent shader & Particles issue