Foreign Keys IDENTITY

I've posted this in the general database forum as well but think it is more sql server specific. I have three tables as below. My problem is that when I insert anything into has_quote, cat_ref and cust_id are both null. Any ideas on how to get round this? Thanks


Code:

CREATE TABLE Item (
cat_ref INT IDENTITY(1,1) PRIMARY KEY,
descrip VARCHAR(50),
date_added SMALLDATETIME,
cat_type VARCHAR(20),
contract VARCHAR(10),
cost_price SMALLMONEY,
supplier_name VARCHAR(20),
supplier_phone VARCHAR(20))


CREATE TABLE has_quote (
quote_id INT IDENTITY (1,1) PRIMARY KEY,
installation_charge SMALLMONEY,
date_of_quote SMALLDATETIME,
commercial_markup SMALLMONEY,
service_desk_contact VARCHAR(20),
category INTEGER,
date_last_pricecheck SMALLDATETIME,
cat_ref INT FOREIGN KEY
REFERENCES Item(cat_ref),
cust_id INT FOREIGN KEY
REFERENCES Customer(cust_id))

CREATE TABLE Customer (
first_name VARCHAR(10),
surname VARCHAR(10),
customer_phone VARCHAR(20),
contract VARCHAR(10),
location VARCHAR(20),
email VARCHAR(50),
cust_id INT IDENTITY (1,1) PRIMARY KEY)