postMessage and targetOrigin

Is it possible to specify more than one targetOrigin url, if using postMessage with an iframe?

I know I can specify one url:
otherWindow.postMessage(message, 'http:example.com');

or unlimited url's with an *:
otherWindow.postMessage(message, '*');

But is what if you wanted to specify 2 or 3 url's? Is that doable?

no, use a star. the bigger security concern is sniffing out incoming messages in the event handler...