[bug] Adding Cards issue

I'm new to the site, and having issues adding cards to my MTG inventory.  What happens is I'll type in a card, verify that it's on the popdown list, tab over to "count", enter the number, tab again, and press space or enter to add those cards to my inventory.

Twice now, I get to my 32nd unique card in the list and I get a little red box telling me that the card could not be found and couldn't be added.  This persists after leaving the inventory screen and returning.

Oddly, it does actually add the card when I hit refresh, there just seems to be negative feedback when I do so.

Browser: Opera 10 on Debian Linux.