[support] Drush 6 and Drupal 8?

I have installed DRush 6 and a fresh Drupal 8 site (once thru git and once thru zip) and get the following error when I do "*drush up*" * Fatal error: Call to undefined function _update_cache_clear() in C:\ProgramData\ Drush\commands\pm\update_info\drupal.inc on line 63 * Anyone else had this experience? Trying to determine if this is an issue to be reported. Thanks Tony -- *Anthony Stefan Maciejowski* *www.Tony-Mac.com*