What window.postMessage emulation options are there for IE7?

I'm aware of the hac开发者_JS百科ks using hash tags, however, I need bi-directional communication with larger payloads and higher throughput. Are there any Flash/ActiveX/etc options that make this possible?

---

Jquery windowMsg plugin provides a good all browser compliant solution.

See an example:

http://iterativo.wordpress.com/2010/03/24/using-jquery-to-communicate-between-browser-windows/

A link to the plugin code:

http://go-trendy.com/javascripts/jquery.windowmsg-1.0.js?1279359701

---

EasyXDM is the closest I can think of, although it isn't a postMessage() polyfill, so would need a lot of work. Also as at Sept 2012, there is a note saying that EasyXDM isn't working for IE6/IE7 - YMMV.