It appears that the UDP packets generated by the traceroute utilities are malformed - illegal header length. I have posted an article of my findings: http://campus.murraystate.edu/tsm/tsm352/LinuxStuff/TraceRouteBug.doc I would appreciate hearing about any other information anyone might have on this subject. Thanks, JMcLaren - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html