PayPal was unable to process payments for 4 hours on Sunday morning, January 2, 2005. eBay's statement on the Systems Announcement Board said payment processing for PayPal was unavailable from 04:40 to 08:37 PST. At the same time, PayPal experienced a system failure when processing credit/debit card transactions through its partner, Wells Fargo, according to a second announcement. The failure affected every credit/debit card transaction during that period, including Visa, MasterCard, American Express and Discover Card. The situation did not affect users of the PayPal Debit card or Switch Solo credit cards users out of the United Kingdom.

"The Wells Fargo processing error could temporarily impact user credit/debit card limits and the ability of users to make future purchases. Users were not financially impacted when using their credit or debit (check) cards for transactions during this period as a result of this issue. We are working closely with Wells Fargo to resolve this matter as quickly as possible."

http://www2.ebay.com/aw/announce.shtml#2005-01-02084142