After looking into the source, I found this brilliant comment in acng.conf.in:
# There some broken HTTP servers and proxy servers in the wild which don't # support the If-Range header correctly and return incorrect data when the # contents of a (volatile) file changed. This also applies to incomplete # resumed downloads. Setting VfileUseRangeOps to 0 disables Range-based # requests (using purely If-Modified-Since and requesting the complete file # instead, if changed). Setting it to a negative value removes even this check # and means fetching the whole file from the beginning. # # VfileUseRangeOps: 1 The thing is that acng is such a broken HTTP proxy server *itself*, it does weird thing with If-Range header exactly as outlined in this comment. After setting VfileUseRangeOps to 0 things started working. This obviously needs to be fixed still. /mjt
