Unwrap light information to uv space?

Hello everybody

How can I access the light information in the surface part of the shader?

Code (csharp):

1. #pragma surface surf SimpleLambert
2.  
3.       half4 LightingSimpleLambert (SurfaceOutput s, half3 lightDir, half atten) {
4.           half NdotL = dot (s.Normal, lightDir);
5.           half4 c;
6.           c.rgb = s.Albedo * _LightColor0.rgb * (NdotL * atten * 2);
7.           c.a = s.Alpha;
8.           return c;
9.       }

I'd like to use c.rgb in the surface part of the shader, where I specify o.Albedo, etc.
So that I could write there something like this:

Code (csharp):

1. float4 light = c.rgb;

Any ideas on how to do so?

Many thanks in advance!