URL sanitizer: disabled uppercase letters in URL hex character codes (it was causing conflicts with the Windows/Apache 2.2 alt namespace separator). Thanks Techokami for finding and reporting this bug.
# 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>