DHCP forwarding and multiple subnets on a single interface.

[Frances Albemuth]

 Hi all,

  First post to the list, so apologies in advance if my etiquette
isn't appropriate.  I'm using the ISC DHCP server in a rather vanilla
configuration right now and I'm moving towards the addition of new
interfaces over which DHCP will be served via forwarding.  I would
like to be able to map multiple address blocks to a single interface
and have the DHCP server make offers based on utilization of pools,
but I see no way to do this.  It seems to me that the server sees the
source address of the interface from which the request was forwarded
in therefore makes an offer from that pool (subnet a.b.c.d).  It's not
obvious looking at the man file (and frankly seems counter-intuitive)
that you can specify a range or pool inside of a subnet declaration
that lives outside of said subnet.  Has anybody got a way of
accomplishing this?

 TIA,

  -FC