.htaccess version numbering
ElegantSolutions - July 3, 2009 - 20:15
The following line appears in the bottom of the .htaccess file of the 6.13 drupal core release.
# $Id: .htaccess,v 1.90.2.3 2008/12/10 20:04:08 goba Exp $
Does this identify the version of .htaccess ?
If so the 6.12 drupal used the same version, therefore the current version of .htaccess does not need to be copied during the upgrade, right?

Right. See also the last
Right.
See also the last paragraph of http://drupal.org/drupal-6.13
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Small glich in the last paragraph
As a matter of fact, the last paragraph is inacurate. The default settings.php file did change.
adding:
ini_set('session.use_cookies', 1);see: http://cvs.drupal.org/viewvc.py/drupal/drupal/sites/default/default.sett...
http://www.xmacinfo.com