类型参数不能用作限定符

VB.Net2005

Simplified Code:

 MustInherit Class InnerBase(Of Inheritor)
End Class

MustInherit Class OuterBase(Of Inheritor)
    Class Inner
        Inherits InnerBase(Of Inner)
    End Class
End Class

Class ChildClass
    Inherits OuterBase(Of ChildClass)
End Class

Class ChildClassTwo
    Inherits OuterBase(Of ChildClassTwo)
End Class

MustInherit Class CollectionClass(Of _
        Inheritor As CollectionClass(Of Inheritor, Member), _
        Member As OuterBase(Of Member))
    Dim fails As Member.Inner ' Type parameter cannot be used as qualifier
    Dim works As New ChildClass.Inner
    Dim failsAsExpected As ChildClassTwo.Inner = works ' type conversion failure
End Class
 MustInherit Cl