3D Text Shader with light

Hi,

I'm trying to have text dislaying on a wall. So I use a 3D text gameobject with this shader i have found on the wiki :

 Shader "GUI/3D Text Shader" { 
 Properties { 
    _MainTex ("Font Texture", 2D) = "white" {} 
    _Color ("Text Color", Color) = (1,1,1,1)   
 }
 
 SubShader { 
    Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" } 
     Lighting Off  ZWrite Off Fog { Mode Off }
    Blend SrcAlpha OneMinusSrcAlpha 
    Pass { 
 
       Color [_Color] 
       SetTexture [_MainTex] { 
          combine primary, texture * primary 
       }         
 }    
    }     
 }
 

The problem is, I'd like to have the text being affected by light. i tried to turn "Lighting on" but then unity warns me that the mesh of the 3d text has no normals.

Is there a simple way to circumvent this problem ? By adding normal to the the mesh, or by modyfing the shader ?

I don't know much about shaders (and it seems damn complicated to learn from scratch), so i am quite stuck with this one...