Exiting SCORM Course in Firefox

Hi all-

I'm running into a problem in Firefox while testing my SCORM course in my LMS.  In IE and Chrome, when I use the X on the toolbar, the system recognizes that I've closed it, and sends the user back to the LMS to select the next section of the course to work on.  In Firefox, it closes the window with the course, but then freezes every time and the user is stuck (in my testing until they shut down firefox in the task manager). My LMS vendor says it has to be a setting issue within captivate, but I can't figure out what to change. I guess it cold also be a settings issue on my machine in Firefox?

Any ideas why it would work everywhere BUT firefox? Or ideas for how I can work around it?

Colleen