These are the answers to some of the queries from google that end up here:
ActiveXObject’s in Firefox:
Only IE supports ActiveX.
Microsoft XML (MS XML) Parser in Firefox:
The Microsoft XML Parser objects are ActiveX and thus will not work in Firefox. However, two of the mostly used objects are availble. See the next answer.
XMLHTTPRequest in Firefox:
IE and FireFox/Opera/Safari have different implentations of XMLHTTPRequest. IE uses the object in their XML Parser, while Firefox, Opera (8.0) & Safari uses XMLHTTPRequest. It is initialised like this:
var obj = New XMLHTTPRequest()
See this article from Apple for more information.
Download MS XML Parser 5.0:
To my knowledge there is no public download available of MS XML Parser version 5.0. It is only included in the latest version Microsoft Office.
XML Sniffer:
See my XML sniffer code here. Cross browser version coming soon.