Configured the IPs: Host: 192.168.56.1 XP Guest: 192.168.56.2 Ubuntu Guest: 192.168.56.3
Another strangeness: tracert on Host to IP 192.168.56.2 shows it going to the internet (through different interface), although route PRINT 192.168.56* shows the right interface!!
Guests can ping each other, host sees no one. Tried turning off the win firewall. Running VB v.4.0.12