not fixed length of the most viewed posts?

Hi! Thank you for your really east-to-use plugin, love it!
Have some troubles with PVC_GET_MOST_VIEWED_POSTS() function:
this is supposed to be a wrapper for get_posts() but it seems to me that ‘numberposts’ doesn’t work. I’ve set 5 but it’s showing all viewed posts.
I’d be very grateful to hear form you any ideas of solving the trouble!
Thank you in advance!