Why can I only use SSI with relative path?

I just read a little tutorial on SSI and managed to show what I wantedbut I'd like to use an absolute path to point at this file, but for some reason I can only do it with a relative path. Am I doing something wrong?

<!--#include virtual="/menubar/bar.html" --&开发者_开发知识库gt;

Works

But when I use:

<!--#include virtual="http://chusmix.com/menubar/bar.html" -->

I get this error: [an error occurred while processing this directive]

Thanks!

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Typically SSIs must refer to local filesystem paths. What you are trying to use isn't an absolute filesystem path - it's an HTTP URL.