Ribbed Frosted Glass Issue.

Hi all, I am confused with a material I have created. Its a ribbed, frosted glass and it works fine but its other normal glass objects behind it thats the issue, they appear as though the ribbed glass doesnt exist.

Any thoughts. The attached image shows an object behind the glass on a table but it appears as though its infront.

For translucent objects, you have

image

Objects with a lower index are shown in front, negative numbers are also possible.