MultiVoIP isn't responding to traceroute packets

The MultiVoIP will respond to ICMP echo requests, but not to UDP datagrams.

The MultiVoIP does not respond to traceroute packets if they are sent as UDP datagrams. Newer versions of traceroute, however, do allow the use of ICMP echo requests (-I option) or TCP SYN probes (-T option) instead.

http://linux.about.com/library/cmd/blcmdl8_traceroute.htm

http://linux.die.net/man/8/traceroute

A Windows utility that is similar to traceroute, called tracert, might see the MultiVoIP respond since tracert uses ICMP echo requests with varying Time-To-Live (TTL) values to map hops.

Use ping (ICMP echo requests) instead if you are not able to get traceroute to work.