All necessary code is included with the module. The hashing functionality is
backported as the include file from Drupal 7 with minor changes.

This module requires PHP 5.2.4 as a minimum version (the same as Drupal 7).

During installation all existing user passwords will be converted to the
more secure form. This is a lengthy process. Using drush expect a
conversion time on the order of 3-5 minutes per 10,000 users. Using
the modules page, a batch process will run and will take at least as long.

Once you have installed this module, all password hashes will be converted.
You will not be able to disable or uninstall it except via upgrading to
Drupal 7. Test this on your developent copy of your site first. You have
been warned.

Note the enable hook tries to convert all existing user passwords.  If you have more
than a thousand users a batch job will start when the module is enabled if enabled
via the modules page.  If enabled via drush or with <= 1000 users, no batching
wiil be performed.  You may need to increase the allowed PHP memory if enabling
via drush for very large numbers of users.

Please test everything on your development copy of the site first!

A core patch is also included with the module as user_load.D6.patch
This patch is not needed for typical sites, but may be required for
certain contrib modules that perform user registration with an external
service or manipulate the user registration flow.