virtualbox: no TCP traceroute
Yes, if you want to have your guest respond to unsolicited ICMP signals, you will have to configure port forwarding for it.
That said, VBox port forwarding for ICMP is pretty weak, especially when run on linux Hosts (since appearently listening for ICMP requires root, and vbox runs under standard user priv).
see here for instructions and discussion on the topic: http://www.linuxjournal.com/content/tech-tip-port-forwarding-virtualbox-vboxmanage