dhcp classless routes

[Patrick Welche <prlw1%cam.ac.uk@localhost>]

I can see how to write the equivalent of

  route add -net w.x.y.z/m g.a.t.e

in /etc/dhcpd.conf using the base system's dhcpd and dhcpcd a la
rfc3442. Am I right in thinking that there is no way of doing the
equivalent of

  route add -net w.x.y.z/m g.a.t.e -iface

?

Cheers,

Patrick