>What versions of netscape contain built in support for XML? Does IE 4.0 contain built in support for XML?

No.

Here is a previous post from Ken Levy.

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If they had Netscape browser, you could simply do the .transformNode() on the server (like in an ASP) and return HTML, so that the client wouldn't see the XML. You just need either IE5 or just the new MSXML parser on your server, and you can then execute CreateObject("Microsoft.XMLDOM"), and you're done. If you program in Java on the server, you can download the same parser used by IE5 from http://datachannel.com which DataChannel created with Microsoft, same exact interface.
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