Install error for Google Checkout extension = "Notice: Undefined property: CRM_Core_Extensions_Extension::$id in CRM_Admin_Page_Extensions->browse() (line 169 of C:\wamp\www\sites\all\modules\civicrm\CRM\Admin\Page\Extensions.php)."

When I click on the "Install" button for the (org.civicrm.payment.googlecheckout) package, it appears to install but fails to activate the package or add to the civicrm_option_value TABLE in the civicrm DBMS. I get the logged error shown in the attached file "civiCRM 4.0.5 Google Checkout Installation log file error.png" - Notice: Undefined property: CRM_Core_Extensions_Extension::$id in CRM_Admin_Page_Extensions->browse() (line 169 of C:\wamp\www\sites\all\modules\civicrm\CRM\Admin\Page\Extensions.php).

And hence the list of extensions still indicates Google Checkout's status as "Available" vs. "Installed" even though it moved the Google package to the top of the extension selection list - also not green highlighted (attached file named civiCRM extension selection List Panel.png)

The Google Checkout Package HAS been downloaded and copied to the correct folder under "C:\wamp\www\sites\default\files\civicrm\civiCRM_ext" (pictured in the attached file: Google Checkout Installation - package created.png).

In civiCRM 4.0.4, the same extension installation broke sooner (the path name for the installation location had incorrect slash parsing ("/"). That looks correct now. But the new extension installation for the Google Checkout extension doesn't set the table object id correctly and hence fails to insert the two rows in the options tabel. ? The other 4 packages installed fine.