urgent: ALTER TABLE!

I have a table "Corres". "no_control" is a column
autonumeric type and the primary key with an index
named "IndexP". "Corres.no_control" is a foreing Key into
the tables "Copia" and "Destinatario". I have two
constraints:
"Corers1" = Destinatario.no_control to Corres.no_control
(update cascade, delete cascade)
"corres2" = Copia.no_control to Corres.no_control (update
cascade, delete cascade)
I have to made a macro that clean the table corres and
restore the "no_control" to 1.

I have this steps:
1. Delete * from corres
2. alter table destinatario drop constraint corres1
3. alter table copia drop constraint corres2
4. ALTER TABLE CORRES DROP constraint [IndexP]
5. ALTER TABLE CORRES DROP [no_control]
6. ALTER TABLE Corres ADD no_control Numeric,Constraint
PrimaryKey Primary Key (no_control)
7. ALTER TABLE Destinatario ADD CONSTRAINT corres1
FOREIGN KEY (no_control) REFERENCES Corres (no_control)
[oN DELETE CASCADE ON UPDATE CASCADE]
8. ALTER TABLE Copia ADD CONSTRAINT corres2 FOREIGN KEY
(no_control) REFERENCES Corres (no_control) [oN DELETE
CASCADE ON UPDATE CASCADE]

the problem is:
In the step 6 I have to create the column no_control with
autonumeric type not Numeric but I do not know the reserve
word.
In the step 7 and 8 the part [oN DELETE CASCADE ON UPDATE
CASCADE] don't work.

Est-ce quequ'un pourrait m'aider s'il vous plait???
Merci en avance
Carmen