OK - now I am confused. I found a perl based http proxy (named "http::proxy" funnily enough) that has filters to change both the request and response headers and data. I modified the response from the web site to lowercase the urls in the html (actually I lowercased the whole response) and the data that wget put on disk was fully lowercased - problem solved - or so I thought.
However, the case of the files on disk is still mixed - so I assume that wget is not using the URL it originally requested (harvested from the HTML?) to create directories and files on disk. So what is it using? A http header (if so, which one??). Any ideas?? Cheers Allan