No subject

I'm doing some research into which of Entity Framework and (fluent) nHibernate is the best fit for a project. And I've stumbled into some mapping problems. I'm hoping someone here can help me out with a quick solution :)

Here are my entity classes:

public abstract class DisplayItem
{
    public virtual int Id { get; set; }
    public virtual string Name { get; set; }
    public virtual string Description { get; set; }
}

public class Link : DisplayItem
{
    public virtual Node FromNode { get; set; }
    public virtual Node ToNode { get; set; }

    public Link()
    {
    }
}

public class Node : DisplayItem
{
    public virtual IList<Link> LinksFrom { get; set; }
    public virtual IList<Link> LinksTo { get; set; }

    public Node()
    {
        LinksFrom = new List<Link>();
        LinksTo = new List<Link>();
    }
}

I tried first to use the automatic mapper, but that did not work at all. It did create the database and saved data, but the data was not connected correctly. I think the problem comes because a Link contains two instances of Node

I then tried manually mapping it, here is the code I used:

 public class LinkMap : ClassMap<Link>
{
    public LinkMap()
    {
        Id(x => x.Id);
        Map(x => x.Name);
        Map(x => x.Description);
        References(x => x.FromNode);
        References(x => x.ToNode);
    }

}

class NodeMap : ClassMap<Node>
{
    public NodeMap()
    {
        Id(x => x.Id);
        Map(x => x.Name);
        Map(x => x.Description);
        HasMany(x => x.LinksFrom)
            .Cascade.All();
        HasMany(x => x.LinksTo)
            .Cascade.All();
    }
}

Any Idea what I'm doing wrong?