I have a test server running CentOS, and changing the
Vary header there through PHP via:
works as expected (it's added to the
Accept-Encoding value that Apache already adds by itself). On the Ubuntu 10 LTS production server it does not. I tried to search the web for answers, but couldn't find any. Even setting:
header('Vary: Accept',true); // forces the header to be replaced
won't change the
Vary header. Any help would be appreciated.
The server is running Apache/2.2.14 (Ubuntu) and PHP/5.3.2-1ubuntu4.26.