Yuichiro Ori <ori@ose.minolta.co.jp>  wrote:

Yuichiro> After boot, ifconfig -a gives,

Yuichiro> ae0: flags=8822<BROADCAST,NOTRAILERS,SIMPLEX,MULTICAST> mtu 1500
Yuichiro> 	address: 00:80:19:07:18:de
Yuichiro> 	media: manual

It seems good to me.

Yuichiro> so it looks fine excpt "media: manual". Does this
Yuichiro> mean this media is not supported?

No. IIRC, it indicates the card has no auto media selection,
e.g. AUI and UTP.

Yuichiro> ifconfig inet 192.168.1.2 255.255.255.0 does not
Yuichiro> work and gives the error like,

It'd be as below.  Note the "netmask" keyword.

ifconfig inet 192.168.1.2 netmask 255.255.255.0

Yuichiro> ifconfig:SCICGIFLAGGS:inet:Device not configured.

Yuichiro> Am I doing something wrong? or Is this card not
Yuichiro> supported for NetBSD?

I don't know if the card is supported, but some info about
supported ethernet card is in the NetBSD/mac68k Ethernet
Status page in the MacBSD docs page.

http://www.macbsd.com/macbsd/macbsd-docs/index.html

Cayman's Gatorcard PDS for SE/30 is listed there, so I think 
your card would work.