Hi Lum-chan,
It seems your DNS settings aren't right. I assume that your XP clients get DNS via a DHCP lease from the gateway SME ? If so, why run two DNS domains internally ? (sme-server2.local and sme-server.local) Both machines should really be on the same DNS domain (choose one) so that they become:
gateway.sme-server.local and satan.sme-server.local or similar.
Then add an entry into each SME's host table about the other machine.
You'll need to reconfigure this through the console.
Damian