On Solaris,

# route add default 131.162.160.1
add net default: gateway 131.162.160.1

$ netstat -r

Routing Table:
  Destination           Gateway           Flags  Ref   Use   Interface
131.162.160.0        chaos                 U        3  13670  hme0
BASE-ADDRESS.MCAST.NET chaos                 U        3      0  hme0
default              vlan-160.acadiau.ca   UG       0  33899
localhost            localhost             UH       0   4036  lo0

# netstat -nr

Routing Table:
  Destination           Gateway           Flags  Ref   Use   Interface
131.162.160.0        131.162.164.5         U        3    477  hme0
224.0.0.0            131.162.164.5         U        3      0  hme0
default              131.162.160.1         UG       0      2
127.0.0.1            127.0.0.1             UH       0   4397  lo0

documented on: 2000.10.20 Fri 20:59:58