An anonymous reader sends this excerpt from BetaBeat:“The Department of Homeland Security appears to have shut down the ability to use Dwolla, a mobile payment service, to withdraw and deposit money into Mt. Gox, a Bitcoin trading platform. … A representative for Dwolla told Betabeat that the company is ‘not party’ to this matter and encourages those with questions to reach out to Mt. Gox or the DHS. ‘The Department of Homeland Security and U.S. District Court for the District of Maryland issued a ‘Seizure Warrant’ for the funds associated with Mutum Sigillium’s Dwolla account (a.k.a. Mt. Gox),’ he said. ‘In light of the court order, procured by the Department of Homeland Security, Dwolla has ceased all account activities associated with Dwolla services for Mutum Sigillum while Dwolla’s holding partner transferred Mutum Sigillium’s balance, per the warrant.'”
However you can still make USD cash deposits using BitInstant.com and USD withdrawls thru Paypal.com (%9 fee).