Facebook icon at left sidebar with width error

Please, take a look at this page. The facebook icon is with a width problem, it not appears 100%. Some one here can tell me what I should to do?

please, take a look:
http://grupobms. com. br/store/products/software-gerenciamento-comercial-empresarial/

tks!

http://wordpress.org/extend/plugins/twitter-facebook-google-plusone-share/