upgrade issue from 1.0 to 1.1 with self referential object

Hi
this used to work in version one but is causing me problems when i updated to 1.1 it seems like the wrong column for a refrence is being pulled through in the mappings

my mapping files are as follows
for a category i have
HasMany(Function(x) x.Children).Inverse().OrderBy("DisplayOrder").KeyColumn("Parent_id").Cascade.All().LazyLoad()
HasMany(Function(x) x.AllChildren).Inverse().OrderBy("DisplayOrder").KeyColumn("Parent_id").Cascade.All().Where("IsHidden = 0").LazyLoad()
References(Function(x) x.Parent)
HasMany(Function(x) x.MerchandisedProducts).Inverse().LazyLoad().Cascade.All() 'this is a productVsCategory collection

and for a productvscategory i have
Id(Function(x) x.ID)
References(Function(x) x.Product)
References(Function(x) x.Category)
Map(Function(x) x.RankOrder)

from exposing the schema i can see the issue is that in the productvscategory table it is saving the foreign key now as parent_Id to link back to a category instead of Category_Id any help/guidance would be appreciated