Ajax/xml cross-domain script

Hello, We are looking for javaxript/ajax/xml guru who can complete following task: - On page load (or other event), javascript is executed. - This javascript will call (using Ajax or other method) a server-site (PHP/Perl) script with some parameters in the URL. - The server-side script will fetch some html/javascript code stored in the database. The returned code will be always different, depending on variables passed to the server-side script in the URL. - The returned code will be placed on the page and if it’s javascript, also executed. - This has to work in cross-domain environment. The initial page which contains javascript will be loaded on [login to view URL] It will open connection and call server-side script, for example from [login to view URL];param=2. This server-side script will pull and return html/javascript code form database and this will be returned and run again on [login to view URL] (without reloading the page, for example using Ajax). - This has to work on SSL connection as well. Both domainAAA and domainBBB can be used either as simple http or https. - If the returned code is html, it should be placed on page. This will be usually <IMG> tag with 1x1 pixel image. - If returned code is javascript, it has to be executed. This can be done for example using “eval” or other function (example: [login to view URL]). - The returned code can be mix of HTML and javascript. In this case, javascript has to be executed again. - The returned code can contain link to external javascript. Again, it has to be executed the same way as if it was placed on the original page.