Trying to use grunt-sass and it can't find compass

i am trying to write a grunt script to watch and compile my sass files. I have decided that i would do it with grunt-sass instead of the usual grunt-contrib-sass simply because i don't have to worry about installing Ruby and all the gems on my PC (plus it is much faster).

I have got it set up to watch my files and compile the sass, but i am getting an error:

Warning: E:\SVN\Brand Work Files\TM/style/v4/sass/_core/base:1: error: file to import not found or unreadable: "compass/reset"

I have already installed Ruby 1.93 and the latest compass (1.0.0.alpha.19) through the command line - how do i reference these compass files so that i don't get this error anymore?

Here is my Gruntfile:

module.exports = function(grunt) {

    grunt.initConfig({
        pkg: grunt.file.readJSON('package.json'),
        watch: {
            files: ['./style/v4/sass/**/*.scss'],
            tasks: ['sass:uk'],
            options: {
                spawn: false,
            },
        },
        sass: {
            uk: {
                options: {
                    outputStyle: 'compressed',
                    sourceComments: 'map'
                },
                expand: true,
                cwd: './style/v4/sass/',
                src: ['*.scss'],
                dest: './style/v4/css/',
                ext: '.css'
            }
        }
    });

    grunt.loadNpmTasks('grunt-contrib-watch');
    grunt.loadNpmTasks('grunt-sass');

    grunt.registerTask('default', ['watch']);

};

Yep, you're absolutely right. Shame really because grunt-sass absolutely flies when compared to normal sass.