NAT Traversal?

After fiddling with the racoon.conf, I was able to tunnel through to our SonicWall SOHO-3. When I try to ping the router, though, I get the following on the server log: "NAT Discovery : Peer IPSec Security Gateway doesn't support VPN NAT Traversal". I got the same message when I tried VPN Tracker. Any way around this (other than connecting directly to my single public IP)? Thanks.