I encountered some similiar problems in the archives, but never a
solution.  Here's my report.  Yesterday I sat down to help a friend get
NetBSD going on his truckload(almost literally, he went to a school
district auction) of old Macs.  He's got Classics, and LCs, and LCIIs,
and LCIIIs for the most part, with some IIsis and one IIci throw in.  We
decided to start with a couple of LCIIs since they were already
reasonably assembled and we already had some commslot ethernet cards.
We got everything installed just great and they're up and running for
over 10 hours now without a hitch.  The one problem is that both of them
had the ethernet interface probed and attached multiple times.  On the
one I took home I've got:
sn0 at nubus0 slot a: Macintosh LC Ethernet Adapter
sn0: Ethernet address 00:01:98:34:a2:d9
sn1 at nubus0 slot c: Macintosh LC Ethernet Adapter
sn1: Ethernet address 00:01:98:34:a2:d9
sn2 at nubus0 slot e: Macintosh LC Ethernet Adapter
sn2: Ethernet address 00:01:98:34:a2:d9

He's got one with an ae card in it that probed and attached 5 times!
That's right ae1-5.  Now I can ifconfig one of these interfaces and
start using it, I've been using sn2, and it works fine.  However, it's
obviously not desirable in the long run for these machines to exhibit
this behavior.  Is there any info I can provide to help fix
nubus_attach() not to find some many instances of these devices?
BTW, the OS version is:
[bandix@gurney]% uname -a
NetBSD gurney 1.5 NetBSD 1.5 (GENERIC) #0: Sun Nov 19 14:20:10 PST 2000
root2@c610:/usr/cvs/src/sys/arch/mac68k/compile/GENERIC mac68k

-- 
Brandon D. Valentine <bandix@looksharp.net>
"Few things are harder to put up with than the annoyance of a
good example."  --  Mark Twain, Pudd'nhead Wilson