[wp-hackers] Problem with AJAX actions

[Jason Maskell]

Hey guys, I'm a bit of a newbie to Wordpress, so pardon me if I've wandered
onto the dev list.

I'm not a newbie programmer by any means, but today I've been taking a first
crack at extending an existing plugin and running into some ajax problems,
probably due to my lack of understanding of how WP does it.

I've registered an action:

add_action('wp_ajax_nzshpcrt_createbucket','nzshpcrt_createbucket');

And the nzshpcrt_createbucket function exists.. My ajax gets hit in the
admin page and sends the request to:

wp-admin/admin-ajax.php
?action=nzshpcrt_createbucket&name=Tester22233&cookie=[snip...]

That returns a simple 0 which tells me I'm not getting the output of the
function back, which should be JSON. So, what have I missed? How do I check
into why Wordpress is not doing what I think it should be doing?

Also, is there any docs on this side of WP? The only bit I found was a
tutorial that gave me the basics, but no reference material.