uncaught exception: Error: Permission denied for to get property Proxy.InstallTrigger

I've disabled all other Facebook-related plugins, tried checking and unchecking "Skip loading Facebook javascript" and have deactivated all Comments Plus add-ons, but I'm getting the error (in Firebug): uncaught exception: Error: Permission denied for <https://www.facebook.com> to get property Proxy.InstallTrigger

When I click to login, the popup shows, but then I get the following message:
An error occurred with Developer Site. Please try again later.

And it generates the permission denied error again.

URL: http://newscubamarketing.com/like-diving-bonaire-like-sea-turtles-like-google-earth-great/
WPMS: 3.3
Comments Plus: 1.3.1

Any suggestions?