I had a flight credit for BUD-LAS, originally purchased in HUF. I wasn't able to rebook over the phone because of the currency, although the agent was able to put my new flights in the system, just wasn't able to ticket and provide a HUF denominated voucher for the remainder. I went to SFO and they were able to ticket the new itinerary and print out a paper voucher for the remainder all in the space of about 5 minutes. The agent said it was actually really easy! Why is there such a gap in capabilities between aa.com, the call centers, and the airport ticket desk? I'm probably going to end up using my HUF denominated voucher by purchasing at the airport as well, since it seems to be the easiest way to do anything non-standard.