get XML from iframe cross domain with jquery

I need a little if help to solve this question. I need to get and XML from another 开发者_JAVA技巧server. My server can't make a request because of firewall. With javascript(jquery), What's the solution to make and ajax call cross-domain? I can make the request on client side but, How to get and xml node? Usign a proxy script does not work for me...

Any idea? Many thanks!

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You cannot access content from another frame that is in a different domain. The only types of requests this works for are <script src=""></script> tags. So you could dynamically add a script tag that points to a cross domain service that generates json and possibly get what you want that way.