Rhyn,
I just registered, logged out, and logged back in to your site. I didn't see that error message anywhere. It's not something I've heard of, and not really sure where it would come from within JFBConnect. We don't have any calendar functionality, and that message is not generated directly from us.
Can you try with another browser, Facebook user, or some other combinations to see if you can narrow down any common factors to recreate the problem?
Hopefully it was just a fleeting error..
Good luck,
Alex