Czuch: Yes, you are right. The act did not specifically ban online gambling, rather it outlawed the financial transactions to gambling providers, which would include direct transactions through credit card etc. (as you state), but also includes transactions through the likes of PayPal.

Hence, as you are experiencing, it is very difficult to get the money into a gambling provider, more so as the overseas providers also check users ISPs to ensure they are not from America.

PayPal is worried that its directors may be arrested if they transact between a US citizen and an online gambling provider. Indeed a fellow scot was arrested in 2006 on this law.
http://scotlandonsunday.scotsman.com/gambling/How-US-gambling-laws-sent.2794677.jp


Fencer, take note and be careful if you travel to the USA