Major underlying changes to namespace handling. Each namespace is handled by its own class which extends Namespace_Default. Much greater customization/pluggability potential, at the possible expense of some code reusing (though code reusing has been avoided thus far). Also a bit better handling of page passwords [SECURITY].
# Used for testing mod_rewrite.
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule (.*) install.php?do=modrewrite_test&str=$1
</IfModule>