Jørn, > As I said in the first email, I control both ends (both the sender- and > the receiver-server). But I do not control neither network-connectivity > or Internet-connectivity at either sites. > > I did try turning of Window Scaling at both ends, but it did not help at > all. It still won't deliver. > > I know there is a Cisco PIX at the senders side. They have already > turned of the ESMTP Fixup (or fuckup if you'd like) "feature" by an > earlier request from me, and that solved some problems. But it seems > like the damn PIX has some other "features" which fucks up some more... > Just don't know what.
It is strange that the sending side transmitted the large data packet (with mail contents) with a DF (don't fragment) bit turned on, yet it is captured as two fragments on the transmitting side. Of these two fragments only the second (smaller) reaches the receiver. Looks like something is forcefully breaking packets despite a DF, and I don't find it unusual that a receiving side reluctantly discards a fragment. Mark
