As far as I'm aware the scripting used on Apache is perle, and ignore the double quote that was a slip of the fingers.
Describing the problem, well thats a bit convoluted but I'll have a go.
When trying to access the
website hosting through a web browser, instead opening the page the browser (in this case IE6) treted it as a file download and downloaded it to a temp directory on the pc before opening it. I contacted support who tracked the problem to HTACCESS, specifically 2 lines of code enabling parsing of HTM and HTML pages. They said that due to changes these lines were no longer needed as the server now automatically parsed all pages (nice of them to give us some warning).
Anyhow they removed the offending code from HTACCESS and lo and behold SSI functionality went as well and now you know as much as I do. Apart from a fair bit of flannel, I've had nothing from them.
Art