SQL 2000: Inserting Multiple Rows Into A Single Table

To anyone that is able to help....

What I am trying to do is this. I have two tables (Orders, and
OrderDetails), and my question is on the order details. I would like
to set up a stored procedure that essentially inserts in the orders
table the mail order, and then insert multiple orderdetails within the
same transaction. I also need to do this via SQL 2000. Right now i
have "x" amount of variables for all columns in my orders tables, and
all Columns in my Order Details table. I.e. @OColumn1, @OColumn2,
@OColumn3, @ODColumn1, @ODColumn2, etc... I would like to create a
stored procedure to insert into Orders, and have that call another
stored procedure to insert all the Order details associated with that
order. The only way I can think of doing it is for the program to pass
me a string of data per column for order details, and parse the string
via T-SQL. I would like to get away from the String format, and go
with something else. If possible I would like the application to
submit a single value per variable multiple times. If I do it this way
though it will be running the entire SP again, and again. Any
suggestions on the best way to solve this would be greatly
appreciated. If anyone can come up with a better way feel free. My
only requirement is that it be done in SQL.

Thank you