Problem installing Drupal 6.22 with Drush
I had a similar problem when trying to install Drupal 6.26 with drush 4.5 and 5.0 (I tried both).

You do not have to create the database.  You can but drush will drop it and re-create it.

I fixed my problem by doing :

drush site-install default --db-url=mysql://drupaldbuser:REMOVED@localhost/drupal-6-25


I used the profile default rather than standard since drupal 6.x uses default as the default profile.  The standard profile is the new default name in Drupal 7.


http://drupal.org/node/1410242#comment-5795114
http://knol.google.com/k/how-to-install-drupal-with-drush