Whoops your session has timed out problem for me (Amazon Payments problem)

[ethical]

First I have gone through and read all the other threads about this problem and tried multiple fixes suggested. My SSL certificate matches, my domain name and I HAVE tried ordering with SSL disabled too with no difference.

I am using the most recent zencart ( 1.3.9g) and the most recent Checkout by Amazon module

I THINK the issue comes down to writting the session/cache info for the store. I have tried testing using database (db) for the cache And file cache and an interesting thing here is NO record ever gets created in the database when I order something.

I have this in my amazon checkout configuration

https://mydomain.com/store/index.php...eckout_success

as well as the same set in the Seller central section of the amazon payments website.

this is my configure.php code in the includes folder and likewise in the admin/includes folder:

  define('HTTP_SERVER', 'http://mydomain.com');
  define('HTTPS_SERVER', 'https://mydomain.com');
  define('ENABLE_SSL', 'true');

  define('USE_PCONNECT', 'false'); // use persistent connections?
  define('STORE_SESSIONS', 'db'); // use 'db' for best support, or '' for file-based storage

  define('SQL_CACHE_METHOD', 'database'); 
  define('DIR_FS_SQL_CACHE', '/home/MYUSERNAME/public_html/demo/cache');

and yes i have the sessions folder set in my ZC admin to

/home/MYUSERNAME/public_html/demo/cache

I tried testing without DB cache (set it to use file) and a session file DOES get created, but the same effect, session timeout when i return from amazon checkout.

please any other ideas?? i would love some help here.

thanks

John