Well, I can't give you a good answer and I would love to see some of the Wise Men comment on your question, but I thought I'd give you a hint that [i]might[/i] work.
It seems that you can include your own scripts into the ajax reply and they will be executed on the client. (
http://weblogs.java.net/blog/driscoll/archive/2009/09/02/inline-scripts-mojarra)
Perhaps you can use this feature to send to the client some script which will do the job you need. I haven't even tried this myself short of re-rendering a fragment of the page that contained a script. It worked. But I haven't experimented more.
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