Running NetBSD 1.3.3 on a sparc4c.  I have an alias address configured
on le0 and it seems to be working properly, but the alias address does
not appear in an ifconfig output as I would expect from past experience
with FreeBSD.

crane# cat ifaliases
192.147.160.201 le0 255.255.255.224
crane# ping 192.147.160.201
PING www.weaselboy.org (192.147.160.201): 56 data bytes
64 bytes from 192.147.160.201: icmp_seq=0 ttl=255 time=0.877 ms
64 bytes from 192.147.160.201: icmp_seq=1 ttl=255 time=1.476 ms
^C
----www.weaselboy.org PING Statistics----
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.877/1.177/1.476 ms
crane# ifconfig le0 
le0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        media: manual status: active
        inet 192.147.160.13 netmask 0xffffffe0 broadcast 192.147.160.31
crane# 

-Doug