Joomla! Documentation™

Use the following UrlToolkit rule to enable clean URLs on the Hiawatha webserver:

UrlToolkit {
    ToolkitID = joomla
    Match base64_encode.*\(.*\) DenyAccess
    Match (<|%3C).*script.*(>|%3E) DenyAccess
    Match GLOBALS(=|\[|\%[0-9A-Z]{0,2}) DenyAccess
    Match _REQUEST(=|\[|\%[0-9A-Z]{0,2}) DenyAccess
    RequestURI exists Return
    Match /index.php Return
    Match ^/component/ Skip 2
    Match ^(/|\.php|\.html|\.htm|\.feed|\.pdf|\.raw|/[^.]*)$ Skip 1
    Skip 1
    Match .* Rewrite /index.php
}

Enable an UrlToolkit rule for a virtual host via the UseToolkit setting:

VirtualHost {
    ...
    UseToolkit = joomla
}