Cannot install Drupal on PostgreSQL

With PHP 5.3.3 and Postgres 8.4 I get this error when running install.php:

Fatal error: Class 'Drupal\Core\Database\Driver\pgsql\Install\Database' not found in /home/chsc/www/drupal8/core/lib/Drupal/Core/Database/Driver/pgsql/Install/Tasks.php on line 74

Call Stack:
    0.0001     328800   1. {main}() /home/chsc/www/drupal8/core/install.php:0
    0.0007     337408   2. install_drupal() /home/chsc/www/drupal8/core/install.php:36
    0.0008     340592   3. install_begin_request() /home/chsc/www/drupal8/core/includes/install.core.inc:79
    0.0763    3117224   4. install_verify_settings() /home/chsc/www/drupal8/core/includes/install.core.inc:310
    0.0769    3117324   5. install_database_errors() /home/chsc/www/drupal8/core/includes/install.core.inc:852
    0.0795    3220076   6. db_run_tasks() /home/chsc/www/drupal8/core/includes/install.core.inc:987
    0.0795    3222892   7. Drupal\Core\Database\Install\Tasks->runTasks() /home/chsc/www/drupal8/core/includes/install.inc:899
    0.1932    3486736   8. call_user_func_array() /home/chsc/www/drupal8/core/lib/Drupal/Core/Database/Install/Tasks.php:135
    0.1933    3486928   9. Drupal\Core\Database\Driver\pgsql\Install\Tasks->checkBinaryOutput() /home/chsc/www/drupal8/core/lib/Drupal/Core/Database/Install/Tasks.php:0

This patch fixes two different bugs and allows the installer to finish successfully.

This seems like pretty basic errors, so I would assume that this problem was already reported, but I couldn't find it in the issue queue.