iPad Emissive Shader

Hey Guys,

I'm working on an iPad app and I wrote a simple shader to produce an emissive (glow) effect on the mesh based on an alpha map. When I apply it in the Editor, it works perfectly as it is supposed to, in either graphics emulation GLES 1.1 or 2.0. When I put the build on the iPad, however, it's not working at all (looks like it falls back to a plain diffuse). Can anyone shed some light on the situation? Below is my shader code:

Shader "FX/Highlight" { Properties { _MainTex ("Base (RGB)", 2D) = "white" {} _EmissiveMap ("Emissive Map", 2D) = "white" {} _GlowColor ("Glow Color", Color) = (1,1,1,1) _GlowStrength ("Glow Strength", Range(0,1)) = 0 } SubShader { Lighting On Material { Diffuse (1,1,1,1) Ambient (1,1,1,1) Emission [_GlowColor] }

     Pass {
         SetTexture[_MainTex] { combine texture }
         SetTexture[_EmissiveMap] { combine primary lerp(texture) previous }
         SetTexture[_MainTex] { ConstantColor(1,1,1,[_GlowStrength]) combine texture lerp(constant) previous }

     }
 }