We are working with paypal payments standard in our website. When users fill up their request in our site and press the paypal button \"Buy Now\" we submit all the variables to
Unfortunately it's impossible by design. And it's not for security, in fact it's a much more cynical reason that they do it:
PayPal gets charged a small percentage of all credit card transactions, so the said feature is in fact a thinly veiled attempt to discourage users from using a credit card.
To top it off there is nothing you can do about it! PayPal's API does not currently have a variable which controls this behaviour available to developers.
You may want to consider a different payment tool if taking credit card payment by default is important to you, although in my opinion money is money.