How to disable Apache http compression (mod_deflate) when SSL stream is compressed
Solution 1:
Now after I got more information about the problem, I should answer my own question. This is a reported bug in Apache; Bug 49057 - setenvif should have access to SSL environment variables.
The bug is fixed in Apache 2.4.1 but this is not an option as I'm using CentOS 6.x.
I'll see if I can set no-gzip environment variable through the application instead of the Apache config.