Flash stuck in its own security sandbox

First off, I have two sites, one which is a subdomain of the other.

I'm trying to get a small seed program I've written in flash/actionscript 3 and uploaded to the subdomain to access a PHP file on the subdomain (of course both reside in the directory pointed to by the subdomain settings).

The whole thing works great when run in Flash CS3 from my local machine, but I get a Security Error #2048 when I access the flash file on the server. The php file returns the right response when I access it directly (it will eventually talk to the mysql server), and when the flash file is run from my local PC it accesses the php file on the server just fine. The Actionscript code refers to the php file as 'http://www.subdomain.net/file.php'.

I've published the flash file as a "network access only" .swf (as opposed to local access only), and also placed a crossdomain.xml file at / /public_html and /public_html/subdomain that looks like this:

Code:

---

<?xml version="1.0"?>
<!DOCTYPE cross-domain-policy SYSTEM "http://www.macromedia.com/xml/dtds/cross-domain-policy.dtd">
<cross-domain-policy>
  <allow-access-from domain="*" to-ports="*" secure="false" />
</cross-domain-policy>

---

Anyone have any idea why flash still won't let me out of the security sandbox and allow access to the php file when the .swf is on the server?