Querystring and embed

ok i got this embed stuff

src=“name.swf?id=SOMETHING”

but
i want to be able to add that string
in a getURL()

like

[AS]
var dontknow = “http://www.url.com/$id/something
getURL(dontknow,"_blank");

IN FLASH MX
[/AS]

how can i do that?

thanks