I want to have lan, wan, dmz and wifi as separate, segregated subnets.  I've set this up, but it required me to change the /etc/init.d/S40network file to specifically do an "ifup" for each interface.  I'm trying to avoid having to customize too many files to make upgrades smoother (I'm still on RC2).  Is there a better way to do this?  It'd be really cool if S40network used  a list of interfaces in an nvram variable.