[Plugin: WP Super Cache] Weird Super Cache Problem (WP-Cache Functionality Won’t Work)

I have WP Super Cache installed. The Super Cache function works fine — but the WP-Cache functionality for logged-in users/visitors does not work.

The plugin is generating WP-Cache files…I can look in the cache directory and see files like :

cache/wp-cache-01b5c3aafc1a64f6b600ac8ddac4fc41.html

But when I look at the Cached Contents on the settings page it says:

WP-Cache

* 0 cached pages
* 0 expired pages

and pages when I’m logged in, etc. *always* say “Dynamic page served in blah seconds”

Any ideas?

http://wordpress.org/extend/plugins/wp-super-cache/