Attempts to enter credit card information at our online shop or on your FogBugz On Demand account may have reacted with a server error over the last few hours. This was due to a faulty setting on our credit card processor, and has been corrected. If you were affected by this, you will need to re-enter your credit card information for your payment to actually go through.
This appears to have begun this afternoon (GMT -5), but we did not notice it until just a short time ago. I'm working to fill this hole in our monitoring system, so next time we'll catch it as it happens.