- Pramod Sharma reported and tracked down a bug when doing FTP over a HTTP

proxy. libcurl would then wrongly close the connection after each
  request. In his case it had the weird side-effect that it killed NTLM auth
  for the proxy causing an inifinite loop!

  I added test case 1098 to verify this fix. The test case does however not
  properly verify that the transfers are done persistently - as I couldn't
  think of a clever way to achieve it right now - but you need to read the
  stderr output after a test run to see that it truly did the right thing.

lib/ftp.c

@@ -4146,7 +4146,12 @@ static CURLcode ftp_setup_connection(struct connectdata * conn)
       return CURLE_UNSUPPORTED_PROTOCOL;
 #endif
     }
-
+    /*
+     * We explicitly mark this connection as persistent here as we're doing
+     * FTP over HTTP and thus we accidentally avoid setting this value
+     * otherwise.
+     */
+    conn->bits.close = FALSE;
 #else
     failf(data, "FTP over http proxy requires HTTP support built-in!");
     return CURLE_UNSUPPORTED_PROTOCOL;