I have only the cracked version but it is 5.0.1.114 and from what I can see there is an feature called, "Support automatic refresh rate switch to 24hz for 24FPS content (BETA)"
As shown here:
http://www.arcsoft.com/Forum/forum_posts.asp?TID=8996&OB=ASC
I am not entirely sure if it is turned on as I can't see it in the menu's or it is just not working with my device. Does anyone know further information on this option? Is there a tick option hidden somewhere in the menus?
Cheers.
P.S I do actually have madvr doing the the frequency properly in MPC-HC but sometimes I like to use the nice menu's with my untouched blu-ray collection :)