[LARTC] "RTNETLINK answers: Invalid argument" when adding default multipath route

[mschonfeld@ubp.edu.ar]

Hi everybody, I'm not so glad because of the error I describe in the subject.
I have two internet lines and I want to do equal cost loadbalancing on the two
uplinks to the internet. This is what I do:

ip route add 200.200.200.0/24 dev eth2 table 200
ip route add default via 200.200.200.254 dev eth2 table 200

ip route add 100.100.100.0/24 dev eth1 table 100
ip route add default via 100.100.100.254 dev eth1 table 100

ip route add 200.200.200.0/24 src 200.200.200.1 dev eth2
ip route add 100.100.100.0/24 src 100.100.100.1 dev eth1

ip route add default scope global nexthop via 100.100.100.254 \
                                  nexthop via 200.200.200.254

The last command fails with the message:"RTNETLINK answers: Invalid argument".
I don't know why it fails. I have a 2.4.20 kernel with Julian Anastasov's patches.
iproute2 version ss010824.
Please, help me in this issue. What is exactly what i have to do?
Marcos