Office 2003 International Character Set Toolbar

Some years ago I successfully installed and used the International Character Set toolbar add-ons. More recently, I noticed that although I could still see the toolbars, they no longer worked. I have reinstalled Office & Office proofing and attempted to reinstall the add-ons, but now I cannot see them at all. Attempting to install the XML files directly tells me there is a certificate violation. Any ideas?