.htaccess "Ignore all rules if link starts with..."

In my root folder I have installed wordpress and there is also my submenu.php that can not be loaded with ajax if I use rules for /%postname%/ (in default )

So this is what WP gave me

# BEGIN Word开发者_如何学GoPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /wordpress/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /wordpress/index.php [L]
</IfModule>    
# END WordPress

What do I need to add so that calling

$('#submenu').load('submenu.php?cat=4');

works again?

This is not the way you should be performing AJAX within WordPress.

I suggest you read up on Using AJAX within WordPress from the codex.

I am not really good with htaccess, but this

RewriteRule !^media/ index.php [L]

Will redirect everything except media/* to index, so something like this should work

RewriteRule !^yourscript.php index.php [L]

Note: I agree with Jason there, using it without htaccess is better.