Forcing Gzip Compression

Although if true, that's a pretty sneaky way of bypassing the virus scanner.

Caching proxy servers probably disable it since they need to be able to server uncompressed pages sometimes (and presumably don't want to deal with compressing/uncompressing).

I cant count the number of times one of our clients has complained that something has broken, accused us of being useless because we cant fix it, and we subsequently discover they are running some ancient stinky version of MS proxy on a Windows 98 box somewhere.

Happens ALL THE TIME.

Ignoring cache headers as well - that's a great one. Tell the browser never to remember the page, but it goes ahead and remembers it for the next two weeks. Marvellous.

Yep, I hate that shit more than IE6. At least you know where you are with IE6.

The client correctly sends "Accept-Encoding: x-ps-bzip2" and the server responds with "Content-Encoding: x-ps-bzip2".

GData AntiVirus had a bug once in which it didn't strip out the Accept-Encoding header, tried to uncompress the servers answer (but failed) and then returned the data to the client still compressed, but with the header stripped off

The client assumed uncompressed data and tried to handle the answer that way - needless to say that it had mild difficulties at parsing the compressed XML as if it were uncompressed.

Of course the customer blamed us "GData is perfect - an uncle of an aunt of a friend of mine works there and it's perfect. Fix your crappy software".

This was the last straw of broken AV software altering our data. We stopped using Accept-Encoding or any other additional request header (those are sometimes stripped too) and we use the User-Agent header of the client and the Server-Header of the server to signal compression.

Sadly, but true, this works so far.

I hate, hate, hate AV programs doing stuff like this.

  SetEnvIf Cookie (.*)force_gzip(.*) force-gzip