Category drop-down ignoring category exclusion in shortcode

Hi,

I’ve added the following shortcode to my page:
[fullcalendar category=”-43″]

This successfully excludes the category 43 from the calendar, but the category is still available from the drop-down.

How do I get the drop-down to acknowledge the exclusions in the shortcode?

http://wordpress.org/plugins/wp-fullcalendar/