I've just started using FluentMap and I'm looking to map the same column to 2 properties, as they need the same value. Here's my map:

```
internal class DefaultsMap : EntityMap<Defaults>
{
    internal DefaultsMap()
    {
        Map(d => d.HistoricalValues.Cost).ToColumn("defaultValue");
        Map(d => d.FutureValues.Cost).ToColumn("defaultValue");
        //other mappings...
    }
}

```

This throws the following error: 

```
Exception: Duplicate mapping detected. Property 'Cost' is already mapped to column 'Cost'.

```

So it looks like I can't map the same column to 2 different properties, or is this because the properties themselves are called the same thing (Cost)?