Error found when used with add to facebook plugin..

I love this plugin so much, but recently I found there is one error with other plugin ” add to facebook”

http://chiangmaispecialist.com/events/month/

Please use the mouse hover the calendar..

I found the error disappear after I disable the add to facebook plugin.. Please help.

Supat

http://wordpress.org/extend/plugins/the-events-calendar/