Does the print server have the right gateway configured? Does scrub have any effect (fragments get dropped in some cases if scrub is off - that bit me once with openvpn)? Wouldn't tcpdump tell you more about the packets coming back from it?
I'd probably just use rdr and a TCP proxy on some machine to work around the problem. Print server IP stacks tend to be funny, especially in case of non-1500 MTU. -- Jussi Peltola
