How do I set the correct json headers?

Question

Is there a way in htaccess to ensure the headers for my json are correct?

Update: Does anyone see anything wrong with these headers for json?

Date    Mon, 26 Jul 2010 08:31:11 GMT
Server  Apache/2.2.15 (Unix) mod_ssl/2.2.15 OpenSSL/0.9.7a mod_fcgid/2.3.5 Phusion_Passenger/2.2.15 mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635
X-Powered-By    PHP/5.2.13
X-Pingback  http://brettbarros.com/wordpress/xmlrpc.php
Content-Disposition attachment; filename="json_api.json"
Vary    Accept-Encoding
Content-Encoding    gzip
Content-Length  719
Keep-Alive  timeout=5, max=98
Connection  Keep-Alive
Content-Type    application/json; charset=UTF-8

Specifically, it's working with jquery's getJSON in ie8, ffx, chrome, but not ie7 or ie6...

Answer 1

AddType application/json .json

is a simple way to make all your *.json files being sent with the correct mime type. That, of course, doesn't work, if you create them dynamically in something like a, say, PHP script. In that case, you can add the info inside the script:

<?php
header('Content-Type: application/json');
// ...

Answer 2

You can inspect the headers sent along from the server side using Firebug's Net tab. It shows all the headers for both the request and the response.