Comment by jwr

Well, back in the day I did a lot of network management on ATM and frame-relay networks and MTU-related problems were quite common there. It left me with a habit of always checking packets of different sizes and looking closely for fragmentation-related issues (also ICMP filtering).

But this one is different -- it's not just the packet size that is the problem, it's that certain packets above a certain size get corrupted. Much more difficult to trace, so kudos to the authors. In fact, it seems I was bitten by the exact same problem, but could not trace it down, as I checked and ICMP packets of various sizes passed OK.