.NET Linq Extension: Use a lambda for Distinct() quality comparison

IEnumerableLambdaDistinct

public static class IEnumerableExtensions
{
    public static IEnumerable<T> Distinct<T>(this IEnumerable<T> enumerable, Func<T, T, bool> comparison)
    {
        return enumerable.Distinct(new LambdaEqualityComparison<T>(comparison));
    }

    internal class LambdaEqualityComparison<T> : IEqualityComparer<T>
    {
        private readonly Func<T, T, bool> comparison;

        public LambdaEqualityComparison(Func<T, T, bool> comparison)
        {
            this.comparison = comparison;
        }

        public bool Equals(T x, T y)
        {
            return comparison.Invoke(x, y);
        }

        public int GetHashCode(T obj)
        {
            return 1;
        }
    }
}