Calcfields comes up NULL

Hi, I’m using flash 2004 professional. I’m trying to make a calculated field in a dataset but am having some trouble.

I’ve tried to follow the example used in the flash help.
I have a dataset named “ds”.
I have 3 input text components called “f1” , “f2” and “box1”

In the ds schema, i’ve made 3 items – “price”, “quantity” and “totalPrice”.

All 3 have datatypes set to Number.
“totalPrice” Kind is set to Calculated.

I have f1 bound(out) to ds.price – f2 bound(out) to ds.quantity – and box1 bound(in) to ds.totalPrice.

On the first frame of the movie i have this actionscript:

function calculatedFunct(evt) {
evt.target.totalPrice = (evt.target.price * evt.target.quantity);
}
_root.ds.addEventListener(‘calcFields’, calculatedFunct);

When i run the movie and try to input numbers into f1 and f2, I get “NULL” in box1.

What am i doing wrong?

Thanks in advance, db