Problem with lighting in CG Shader

Hi,

i wrote a simple shader that compose a texture with a color. Now i just want to turn off the lighting but it doesn't work.. Here's my shader:

  Shader "Custom/MyDecalColor" {

  Properties {

      _Color ("Main Color", Color) = (1,1,1,1)

      _MainTex ("Base (RGB)", 2D) = "white" {}

  }

  SubShader {

      Tags { "RenderType"="Opaque" }

      LOD 250

      Lighting Off

  CGPROGRAM

  #pragma surface surf Lambert

  #include "UnityCG.cginc"

  sampler2D _MainTex;

  fixed4 _Color;

  struct Input {

      float2 uv_MainTex;

  };

  void surf (Input IN, inout SurfaceOutput o) {

      fixed4 c = tex2D(_MainTex, IN.uv_MainTex);

      half4 main = tex2D(_MainTex, IN.uv_MainTex);

      c.rgb = lerp (_Color, main.rgb, main.a);

      o.Albedo = c.rgb;

      o.Alpha = c.a;

  }

  ENDCG

  }

  Fallback "Diffuse"

  }

Can somebody help me?