routing problem

["Trevor R.H. Clarke" <retrev_(_at_)_csh_(_dot_)_rit_(_dot_)_edu>]

I've been happily running an openbsd 2.7+ frankenbsd (some stuff 
upgraded here and there) machine as a NAT router for my cable modem. I'm 
 switching to a lightning link (globex) DSL. I received my self-install 
kit in the mail and got it all hooked up. It wasn't working with my obsd 
box so I plugged a win2k laptop direct into the dsl router and it worked 
fine. Some testing and it seems to be a gateway issue. The issue being, 
dhclient is not setting a default route. The lease I'm getting looks 
something like this (IPs changed to protect the guilty):

lease {
  interface "ep1";
  fixed-address 10.1.254.73;
  medium "link0 link1";
  option subnet-mask 255.255.248.0;
  option routers 10.1.240.1;
  option domain-name-servers 10.1.170.2,10.1.128.138;
  option dhcp-lease-time 64800;
  option dhcp-message-type 5;
  option dhcp-server-identifier 10.1.240.1;
  renew 4 2002/6/27 11:28:44;
  rebind 4 2002/6/27 18:13:44;
  expire 4 2002/6/27 20:28:44;
}

Seems to me that the router they send is on a different subnet so when I 
route add default 10.1.240.1 I get a network unreachable error. The best 
I can figure, the network looks sorta like this:

254.73        254.72  240.foo   240.1
+----+          +-----+        +------+
| me |----------| DSL |--------| them |
+----+          +-----+        +------+

Win2k sets the gateway to 240.1 w/o a problem and the dsl router must be 
acting as a bridge. If I force my gateway to be the suspected DSL router 
internal address (254.72) it sorta works but ping times climb from 10 or 
so ms (to random net addresses) up to 2-3 seconds and there is typically 
25%-40% packet loss.

I need some help with this one. Is there a way for me to set my gateway 
to the 240.1 address? Is there some other way around all this?