dhclient ignores received default router IP

[dmoore]

dhclient gets a default router address from a dhcp server. However, it 
fails to apply it to the routing table. A different dhcp client, pump, 
under nearly identical circumstances, does apply it.

dhclient is written to do so via /sbin/dhclient-script, which contains a 
function named add_default_gateway(). However the script never calls 
that function, in my environment. Before I look into it further, is 
there some known background/explanation/fix for this behavior?? When the 
server goes to the trouble of telling dhclient what default router to 
use, how can I make dhclient react to it seriously-- ie put it into the 
routing table as intended?

--------------------
Two different dchp clients (pump and dhclient) running against the same 
dhcp server. Note in both cases the server sends a default router 
address ("Option 3: Router = 192.168.3.2"):


pump - getting dhcp info from a linksys router

Bootstrap Protocol
    Message type: Boot Reply (2)
    Hardware type: Ethernet
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0x7111b3be
    Seconds elapsed: 0
    Bootp flags: 0x0000 (Unicast)
        0... .... .... .... = Broadcast flag: Unicast
        .000 0000 0000 0000 = Reserved flags: 0x0000
    Client IP address: 0.0.0.0 (0.0.0.0)
    Your (client) IP address: 192.168.3.101 (192.168.3.101)
    Next server IP address: 0.0.0.0 (0.0.0.0)
    Relay agent IP address: 0.0.0.0 (0.0.0.0)
    Client MAC address: Intel_41:86:f9 (00:02:b3:41:86:f9)
    Server host name not given
    Boot file name not given
    Magic cookie: (OK)
    Option 53: DHCP Message Type = DHCP Offer
    Option 54: Server Identifier = 192.168.3.2
    Option 12: Host Name = "Knoppix"
    Option 51: IP Address Lease Time = 12 hours
    Option 1: Subnet Mask = 255.255.255.0
    Option 3: Router = 192.168.3.2
    Option 6: Domain Name Server = 192.168.3.2
    End Option
    Padding


dhclient - getting dhcp info from the same linksys router

Bootstrap Protocol
    Message type: Boot Reply (2)
    Hardware type: Ethernet
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0xcfd8e43d
    Seconds elapsed: 0
    Bootp flags: 0x0000 (Unicast)
        0... .... .... .... = Broadcast flag: Unicast
        .000 0000 0000 0000 = Reserved flags: 0x0000
    Client IP address: 0.0.0.0 (0.0.0.0)
    Your (client) IP address: 192.168.3.100 (192.168.3.100)
    Next server IP address: 0.0.0.0 (0.0.0.0)
    Relay agent IP address: 0.0.0.0 (0.0.0.0)
    Client MAC address: Cisco-Li_5e:db:62 (00:14:bf:5e:db:62)
    Server host name not given
    Boot file name not given
    Magic cookie: (OK)
    Option 53: DHCP Message Type = DHCP Offer
    Option 54: Server Identifier = 192.168.3.2
    Option 51: IP Address Lease Time = 1 day
    Option 1: Subnet Mask = 255.255.255.0
    Option 3: Router = 192.168.3.2
    Option 6: Domain Name Server = 192.168.3.2
    End Option
    Padding