can't get cache controle to set an expire date

[Patrick Aljord]

Hi,

This is my nginx config file: http://pastebin.com/TZcfzipk

The problem is that despite setting "expires max" cache sends no
expire date so I must be doing something wrong.
This is what appears as header:

Cache-Control	max-age=0

Any idea how I could fix this?

Thanks in advance,

Pat