实体框架-级联删除未在实体模型中设置

I am using EF 4.0 and am generating my Entity Model (.edmx) file from my database. I have several foreign key constraints for Cascade OnDelete, however, these are not getting set on my associations in my entity model. I click on the association and it shows End1 OnDelete: None. I am using EF 4.0 and am generating my Entity M