Can no longer reach the internet through our proxy server using our global corporate proxy PAC file after updating the PAC file with Microsoft's 'IPv6-Aware Proxy Helper API Definitions' (http://msdn.microsoft.com/en-us/library/windows/desktop/gg308477(v=vs.85).aspx). MS IE 8 and IE 9 work OK, as does Google Chrome. Firefox (our standard browser on non-Microsoft operating systems) is no longer functional with the new PAC file updates.