I found the magic incantation so that OFW 3 will avoid doing
that funky Apple DHCP stuff:

boot enet:0,ofwboot.elf enet:0,netbsd

Note that the netbsd is so that OFW doesn't need to get a filename
for the second DHCP request inside ofwboot.
--
Matt Thomas               Internet:   matt@3am-software.com
3am Software Foundry      WWW URL:    http://www.3am-software.com/bio/matt/
Cupertino, CA             Disclaimer: I avow all knowledge of this message