AbleCommerce Shopping Cart Software

In the "Create Order" process in the Order Admin,
the Qty field was only set to 3 characters:

<asp:TextBox ID="Quantity" runat="server" Text='<%# Eval("Quantity") %>' MaxLength="3"

also the field is a small int and only has a max of 32,000.

Well in most of cases quantities for a single item doesn't even go to that extent. What is the case the in your scenario?

They called me and said that someone wanted a quantity of a 1000
for some item and they could not enter more than 3 digits.
This was an order over the phone.

I think all you need in this case is to remove or extend validation value on quantity box control. Look on receptive product page where they are trying to add it to basket and then HTML for quantity box. Quantity control supports Max value property just change it from 999 to 1000.