Can I make simplemodal contact form post across domains?

I'm using the SMCF Wordpress plugin on this site: http://fingelly.com/

As you can see it uses ajax to post the form fields to get mailed and then updates the modal.

Some of the nav options at the site take you to a 3rd party IDX (real estate listings) provider. For example click on the tabs marked agents and the url changes to fingelly.idxre.com...

As you can see the html is customizable there... I had tried adding the same simple modal contact form to my t开发者_StackOverflow中文版emplate there but encountered a problem because I cannot post using ajax to my wordpress driven site from this other domain.

I understand this limitation is for security reasons to prevent xss. How would you suggest working around it in this case?

For now we've simply removed the contact tab.

If you just need to send information to the server and not worry about the response, you create a hidden iframe on the page and post the data there. You could also make a JSONP call if the data would fit in a GET.