Read flash variable from external domain with javascript

Dear Experts,

Anyone know if it's possible to avoid flash sandbox security to read a variable inside an swf from a javascript?

I don't need to pass the variable from flash to javascript calling some function, I need to directly read a variable inside flash using flash_object.GetVariable("myvariable");

More details:
I have the following.
A Swf file called test.swf with just this two lines:
line 1: var test="12345";
line 2: stop();

then I have a test_readflashvar.js file on the same site with just the flash object code that is written through document.write
and a javascript function testing() that tries to read variable test inside swf.
I have a timer that execute it every x secs.

function write_flash_object(url) {
 //code that write my flash object to document
}

function testing() {
    var o = getFlashMovieObject("flashobj"); //function that search for flash object
    if (o==null || o.PercentLoaded()<100) return;

    alert(o.GetVariable("j"));

    return;
}

Then I add the script to any of my websites (different domain where is located the swf file) <script src="http://target_domain/test_readflashvar.js"></script>

And when I load the page with the included script,  and it executes and the line alert(o.GetVariable("j")); I get the unspecified javascript error (=security access error).

Can anyone give a hint to overpass flash sandbox security control?

Regards,
Luigi.