attachment problem

Hi NG,

I have problem with the qmail programm which doesn't delivery remote
mails. in the mail log file i have a message

"Connected to xxx.xxx.xxx.xxx but connection died (#4.4.2)."

The E-Mail has included a attachment. When i now remove the attachment
in the e-mail, the e-mail will be delivered successful. i have also
checked the communication between the send and receive server with
tcpflow. the communiction start correctly with the HELO and OK sequence
, but as soon the attachment should be transmitted there is no more
network traffic. I have this effect with some other e-mail server too
and i dont't now what is the problem.

I am happy for any pointer or helps.