Entity Framework 4 - Inheritance of TPT in CTP5 functions (code first): renaming a foreign key column in an inherited table

I am trying to convert an Entity Framework xml model to Code First (CTP5). I need to model a hierarchy that is quite consistent with the TPT pattern. The only problem I encountered is that the primary key / foreign key of the inheritance table has a different name from the primary key of the base class.

These are the relevant fields of the tables involved.

CREATE TABLE site.Domains
(
    ID INT NOT NULL PRIMARY KEY,
    Domain NVARCHAR(128) NOT NULL
)

CREATE TABLE site.MainSites
(
    FKDomainID INT NOT NULL PRIMARY KEY REFERENCES site.Domains(ID)
)

CREATE TABLE site.SisterSites
(
    FKDomainID INT NOT NULL PRIMARY KEY REFERENCES site.Domains(ID)
)

this is the code we use when we build the model

var domain = modelBuilder.Entity<Domain>();

domain.HasKey(c => c.Id)
    .ToTable("Domains", "site");

domain.Property(c => c.DomainName)
    .HasColumnName("Domain")
    .HasMaxLength(128)
    .IsRequired();

domain.Ignore(c => c.OldId);

var mainSite = modelBuilder.Entity<MainSite>();

mainSite.Map(m =>
{
    m.ToTable("MainSites", "site");
});

var sisterSite = modelBuilder.Entity<SisterSite>();

sisterSite.Map(m =>
{
    m.ToTable("SisterSites", "site");
});

and this is the generated sql that we get

SELECT 
[Limit1].[C2] AS [C1], 
[Limit1].[C1] AS [C2], 
[Limit1].[Domain] AS [Domain]
FROM ( SELECT TOP (2) 
    [UnionAll1].[Id] AS [C1], 
    [Extent3].[Domain] AS [Domain], 
    CASE WHEN ([UnionAll1].[C1] = 1) THEN ''0X0X'' ELSE ''0X1X'' END AS [C2]
    FROM   (SELECT 
        [Extent1].[Id] AS [Id], 
        cast(1 as bit) AS [C1]
        FROM [site].[MainSites] AS [Extent1]
    UNION ALL
        SELECT 
        [Extent2].[Id] AS [Id], 
        cast(0 as bit) AS [C1]
        FROM [site].[SisterSites] AS [Extent2]) AS [UnionAll1]
    INNER JOIN [site].[Domains] AS [Extent3] ON [UnionAll1].[Id] = [Extent3].[Id]
    WHERE [UnionAll1].[Id] = @p__linq__0
)  AS [Limit1]',N'@p__linq__0 int',@p__linq__0=1

As you can see, it is looking for site.MainSites.Id and site.SisterSites.Id that do not exist. I even tried something like

mainSite.Property(m => m.Id).HasColumnName("FKDomainID");

but, as you can guess, this did not work.

Any suggestion?

Thanks in advance