Does this cache header even make sense?

[talkingnews]

Just a quick random question:

Here's a header:

11/03/2011 15:25:56.005 Cache-Control: no-cache, x-wms-content-size=4129462, max-age=86399, user-public, must-revalidate, proxy-public, proxy-revalidate

Doesn't some of this cancel each other out? I'm trying to work out why my browser/ISP is getting a cached version. Provider says it shouldn't be caching, but it is, and surely user-public, proxy-public cancels out no-cache?

Or at least, that's what I think from having read the docs.