> >GET <http://www.1eden.net/diy> [HTTP/1.1 404 Not
> Found 359ms]
> 
> Despite the 404, Firefox and other browsers still
> load the supposedly non-existing page. 

Apparently you must visit the starting page to get cookies.
Don't mirror /diy, mirror <http://www.1eden.net/> instead.
Don't use any filters.