Drupal HTTP / HTTPS Persistent Sessions?

For some reason my site is not sharing the session between http and h开发者_如何转开发ttps.

My setup,

Drupal 6 with securepages module installed.

You cannsee the example of this here, http://matthewwoodard.com/prducts, if you add to cart you will see the cart empties when it switches to https...any suggestions?

Shot in the dark, are the http pages being cached by drupal/boost?

Be sure to include the following in your settings.php to tell Drupal to allow mixed http and https sessions:

$conf['https'] = TRUE;