Targeting problem?

I’m trying to gain access to my google calendar’s XML feed but am having problems.

The address it gives you for the feed is ‘’ which isn’t an XML file, although it still ‘works’ as a feed if you put that address into your browser.

Why does my browser recognise it as a feed but when I try with PHP it doesn’t recognise it?

What I’m eventually trying to do is get the xml data into Flash using as3, but as I’ve recently found out, there isn’t a way to do it other than using a server-side language to ‘pass’ the data on to it. Hence my current situation.

Any help would be much appreciated. Thanks.