Umm ur error does seem a bit strange, apparently your script is not loading classes properly. This may have something to do with server configuration, rather than script configuration. Can u consult ur webhost and see if they can provide u with more information than you have now? If they can't, I can offer to help u fix the issues tomorrow after a long flight from west back to east coast. In this case, send me ur FTP info.
Edit: Looks like your site may suffer from the same problem as this one, is there a way to remove include_path in your php.ini? This may be the cause of smarty directory not loaded appropriately.
http://www.smarty.net/forums/viewtop...0ade3c1e078a6b