social media links

Hi all, when I add my social icons to my menu bar, the links are automatically taking the address of the page your on. For example.

If your on the homepage (homepage.org), the facebook icon will have a link of: http://www.homepage.org/www.facebook.com/myfacebookpage

and if your on another page, such as the contact page, in my website and click on the facebook icon, the link will look like this:

http://www.homepage.org/contact/www.facebook.com/myfacebookpage

I don’t know why this is happening. Any ideas?
Thanks all!