I have added "share this" buttons to my secure site and now they produce an error when clicked. Errors are mentioned below. Has anyone had this problem before?

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> Blocked loading mixed active content "<http://w.sharethis.com/button/buttons.js>"
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> ReferenceError: stLight is not defined
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> Loading mixed (insecure) display content on a secure page "<http://w.sharethis.com/images/facebook_32.png>"
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