Christos Zoulas suggested:
> # Avoid pcmcia bus space conflicts with the default io space
> # allocation on 12-bit wide busses (base 0x400 size 0xfff).
> options PCIC_ISA_ALLOC_IOBASE=0x300
> options PCIC_ISA_ALLOC_IOSIZE=0x0ff

So I read about this in the pcmcia(4) and options(4) man pages.

And I implemented that and my new kernel did:

 ne2 at pcmcia1 function 0 port 0x300-0x30f port 0x310-ox31f
 ne2: Linksys EtherFast PCM100 Ethernet
 ne2: Ethernet address 01:d4:ff:03:00:20

But still different hardware address. And UDP and ICMP (dns and pings)
work, but TCP (ftp and http) times out (which was same as before).

It seems strange to me to have two port ranges. I am still researching
this.

The working Linux:
>> eth0: NE2000 (DL10022 rev 05): io 0x300, irq 3, hw_addr 00:04:5A:08:78:E1

The working OpenBSD:
>>  ne3 at pcmcia1 function 0 "Linksys, EtherFast 10/100 Integrated PC Card
>>  (PCM100), Ver 1.0" port 0x340/32: irq 9
>>  ne3: address 00:04:5a:08:78:e1
>>  nsphynter0 at ne3 phy 5: DP83815 10/100 integrated, rev. 3

Thank you, Christos, for the reply.

   Jeremy C. Reed
   http://bsd.reedmedia.net/

p.s. I was able to get laptop installed via wi0 with some wireless card I
temporarily borrowed. But no network again since I returned that card
and slip does not work :(