The interesting bit looks to be:
* Telling server to connect to 0.0.0.0:2306
> PORT 0,0,0,0,9,2

Also happens when using -P " ", which I think I read in the libcurl
documentation should pick the default local IP.

Jon.

 C:\Temp>curl -v -P 159.104.223.11 ftp://turnerj > out
* About to connect() to turnerj port 21
* Trying 159.104.223.84... connected
* Connected to turnerj (159.104.223.84) port 21
< 220 Microsoft FTP Service
> USER anonymous
< 331 Anonymous access allowed, send identity (e-mail name) as password.
> PASS curl_by_daniel_at_haxx.se
< 230 Anonymous user logged in.
> PWD
< 257 "/" is current directory.
* Entry path is '/'
* Telling server to connect to 159.104.223.11:2301
> PORT 159,104,223,11,8,253
< 200 PORT command successful.
* Connect data stream actively
> TYPE A
< 200 Type set to A.
> LIST
< 150 Opening ASCII mode data connection for /bin/ls.
* Connection accepted from server
  % Total % Received % Xferd Average Speed Time Time Time
Current
                                 Dload Upload Total Spent Left
Speed
100 2564 0 2564 0 0 82709 0 --:--:-- --:--:-- --:--:--
82709<
226 Transfer complete.
100 2564 0 2564 0 0 11761 0 --:--:-- --:--:-- --:--:--
0*
Connection #0 to host turnerj left intact

> QUIT
< 221
* Closing connection #0

C:\Temp>curl -v -P turnerj2 ftp://turnerj > out
* About to connect() to turnerj port 21
* Trying 159.104.223.84... connected
* Connected to turnerj (159.104.223.84) port 21
< 220 Microsoft FTP Service
> USER anonymous
< 331 Anonymous access allowed, send identity (e-mail name) as password.
> PASS curl_by_daniel_at_haxx.se
< 230 Anonymous user logged in.
> PWD
< 257 "/" is current directory.
* Entry path is '/'
* Telling server to connect to 0.0.0.0:2306
> PORT 0,0,0,0,9,2
< 500 Invalid PORT Command.
* Failed to do PORT
  % Total % Received % Xferd Average Speed Time Time Time
Current
                                 Dload Upload Total Spent Left
Speed
  0 0 0 0 0 0 0 0 --:--:-- --:--:-- --:--:--
0*
Connection #0 to host turnerj left intact

curl: (30) Failed to do PORT
> QUIT
< 221
* Closing connection #0

-----Original Message-----
From: curl-library-bounces_at_cool.haxx.se
[mailto:curl-library-bounces_at_cool.haxx.se] On Behalf Of Daniel Stenberg
Sent: 19 January 2006 11:43
To: libcurl development
Subject: RE: --ftp-port bug with unresolvable names?

On Thu, 19 Jan 2006, jon.turner_at_thomson.com wrote:

> I had been using libcurl 7.15.1 in my own application, but I assumed
> it was the same problem on the older version of curl.exe I had. After
> upgrading to a later version it doesn't crash, but doesn't work with
> the correct name either, but it does when using IP.

Please show us the protocol dump (using -v) from the failing/working
invokes, and it might provide some clues.

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