[BM SS4] Register line sub-features kind of fails

We are upgrading from BM for MicroStation SS2 to SS4 using Oracle Spatial.

We have line feature (Textstege_Line) with two point sub features (Textstege_Text, Textstege_Cell).

When we register them i SS2 we are asked to add Id Generators for both sub-features (which we have). In SS4 we are only asked to add Id Generators for the main features.This result in the primary ID column for the sub-features are listed as a property. We can read Everything just fine, but the features cannot be posted back in SS4.

The primary and foreign key is defined as follows for the sub-features:

alter table TEXTSTEGE_TEXT
  add constraint TEXTSTEGE_TEXT_PK
    primary key (ID);

alter table TEXTSTEGE_TEXT
  add constraint TEXTSTEGE_TEXT_FK
    foreign key (TEXTSTEGE_ID) references TEXTSTEGE_LINE(ID)
      on delete Cascade;