no_shipping parameter not working

I want to collect the buyers details but the following is not working:
[wp_paypal button=”buynow” name=”My product” amount=”100.00″ no_shipping=”0″]

Nor is this:
[wp_paypal button=”buynow” name=”My product” amount=”100.00″ no_shipping=”2″]

Can you offer any help?

Cheers
Mark