Circular Progress Bar iOS Issue with value 0.0f

Hi,

I want a circular progress bar in my app and found an example that uses shader (Transparent->Cutoff->VertexLit). Thanks to the post http://answers.unity3d.com/questions/14770/creating-a-circular-progressbar-timer.html .

This runs fine on Android devices but not on iOS devices. I have even tried on iOS 7 iPad Mini. When we set "_cutoff" value to 0 to show full circle but what the result come up is just a square instead of full circle.

     renderer.material.SetFloat("_Cutoff", 0.0f);

Below is the image having both expected result and the result what I get when giving value 0.0f (any iOS device).

I have event tried values like 0.01 but no help. I have tried different mash filter, like Quad, Cube.

This is the source image I am using.

Texture -> Advanced Alpha is Transparent = true Wrap Mode = Clamp Filter Mode = Trilinear Aniso Level = 1 Max Size = 1024 Format = ARGB 32 bit. No Compression Used.

In Mesh Renderer, Cast Shadows and Receive Shadows are true.

In XCode also I turned off image compression.

Thanks