virtualbox.org

In a vm (WinXP SP2/VBox 2.2.0/NAT),I try ping a host addr 192.168.0.43 use follow command
ping 192.168.0.43 -n 1 -l 245
I found It reply a timeout message,so I try a ping to 10.0.2.2,I found if Package size >1472,seam error found,command is
ping 10.0.2.2 -n 1 -l 1473
I think this may be a bug in VBox 2.2,and I not test it in 2.1.4.
I comfirmed that bug with a vm ubuntu 9.04 with NAT,use follow command:
ping 192.168.0.1 -c 1 -s 245
ping 10.0.2.2 -c 1 -s 1473
the seam problem found.

Ping via NAT is not supported.

A ping does work with NAT, just not everything works properly. You will get a reply if you use a normal ping, but any additional parameters that make it change won't work. You change the packet size, and that won't work. Use Host Interface or Bridged instead.