Is it possible to pay with a pre-paid gift card?


I've received both an American Express and Visa pre-paid gift card, and I've been wondering if it's possible to pay for a subscription to LiquidSky with either of these cards? If I can, then how would I go about doing so? Thanks in advance!

NOTE: I've tried using the American Express card on both the Visa option and the Debit Card option, though both have resulted in "1302: Sorry, the payment was cancelled by the bank."