Change colour of white overlay

First of all, thanks for a fantastic light-weigth plugin!
Please take a look this image: http://tardis1.tinygrab.com/grabs/c5a4cf7dd4df723cc3781031ed29064578006adafc.jpg

This is how the rating plugin works on my site, which has a yellow background. It’s a litle hard to see (because of the yellow or enarly white background), but the overlay on the last half of the 5th star is white (#FFFFFF). Can this overlays colour be changed?

Thanks for any reply in advance!

http://wordpress.org/extend/plugins/ec-stars-rating/