Not on vacation quite yet - a few hours to go. This is really strange. That patch really fixes a bug and should have no negative consequences. The fact that does strongly suggests that there is a bug else where that has been hiding. It is possible to get a tcpdump trace showing the problem? i.e on one client run tcpdump -w /tmp/tcp.trace -iany -s 0 port 2049 & then run the java program on both this and the other client in a way that demonstrates the problem. Then kill the tcpdump, and compress and attach /tmp/tcp.trace ?? I might try to have a look next week to see what is happening.