Vertex shader is correct, but won't run on my hardware?

Question

I can't figure out what's wrong with this shader. It's correct, compiles, and links, but simply won't run on my hardware (MacBook pro w/NVidia GeForce 9400, nothing special). It seems totally GLSL 1.2 compliant

vec4 position;
vec4 new_position;

varying vec3 lightV;
varying vec3 eyeV;
varying vec3 normalV;
varying vec4 ambient;

uniform float angle;
uniform int sens;
uniform vec3 lightSource;

void main(){

    //ambient = gl_FrontMaterial.ambient * gl_LightSource[0].ambient ;
    ambient.x = 1.0;
    ambient.y = 1.0;
    ambient.z = 1.0;
    ambient.w = 1.0;

    //from vertex to light
    //lightV = gl_LightSource[0].position.xyz;
    lightV = lightSource;

    // vertex position in eye space
    vec3 vVertex = vec3(gl_ModelViewMatrix * gl_Vertex);

    //from vertex to eye
    eyeV =  - vVertex;
    //normal
    normalV = gl_NormalMatrix * vec3(0.0,1.0,0.0);

    gl_FrontColor = gl_Color;
    gl_TexCoord[0] = gl_MultiTexCoord0;
    gl_Position = ftransform();

}

Does anything in here seem amiss to anyone? Thanks for any suggestions/advice.