I'm not familiar with that particular problem, although here are the
settings I use for the fcgi buffers (which has worked with me for
files > 1GB being passed on to PHP):

fastcgi_connect_timeout 60;
fastcgi_send_timeout 180;
fastcgi_read_timeout 180;
fastcgi_buffer_size 128k;
fastcgi_buffers 4 256k;
fastcgi_busy_buffers_size 256k;
fastcgi_temp_file_write_size 256k;
fastcgi_intercept_errors on;
fastcgi_pass_header *;

There are also other values, like the document body size which should
be set. You can find information about that in the documentation.

On Thu, Jul 16, 2009 at 1:56 AM, gerryw<nginx-forum@nginx.us> wrote:
> Hello All,
>
> Daniel:
>>Is your FastCGI running on a socket or a port? On Linux, it should be
>>a socket (e.g. unix:/tmp/php.sock) , but on FreeBSD it should be a
>>port (e.g. 127.0.0.1:60000). I found this to be the cause of uploads
>>not being passed back through fastcgi one time.
>
> I was using a port. When I switched to a unix:socket I started getting some data, but it's either garbage or incomplete, because the parser segfaults trying to parse it. Could it be some kind of buffer size issue?
>
> Almir:
>> Did you remember to add enctype="multipart/form-data"?
> Yes.
>
> Thanks,
> Gerry
>
> Posted at Nginx Forum: http://forum.nginx.org/read.php?2,4091,4099#msg-4099
>
>
>