> try to DL
> <http://vivil.free.fr/speedtest/64Mo_faked.iso>
> with 3.40 the extension is .txt in the folder :-(

Well, actually the server replies with a "text/plain" type:

$ lynx --dump --head <http://vivil.free.fr/speedtest/64Mo_faked.iso>
HTTP/1.1 200 OK
Date: Mon, 03 Apr 2006 14:55:31 GMT
Server: Apache/ProXad [Mar 28 2006 05:12:42]
Last-Modified: Sat, 24 Dec 2005 12:44:57 GMT
ETag: "2bd225-4000000-43ad42c9"
Connection: close
Accept-Ranges: bytes
Content-Length: 67108864
Content-Type: text/plain

> no soucy with 3.33 grin !

Yes, because httrack now waits for the server's answer..

You can try this:
--assume iso=application/x-iso

This should give httrack the hint ".iso is actually a known type, so don't
change it with potentially dangerous MIME such as text/plain"