Here is an excerpt from a pf.conf I have doing exactly what you're asking. Use

this as a base. You will need to add more and adjust some to your setup,

bittorrent_tcp_ports is obviously not defined here. And some of the options

for the rules may not really be needed, but they remained after I set it up

and have not tried to remove them yet.  Just remember that for incoming

traffic you do allow on a given interface, you need a "

reply-to ($dsl_X_if $dsl_X_gw) " after the interface name to let the traffic

go back out the way it came and not the boxes default gateway.
lan_net = "192.168.1.0/24"

int_if  = "sis0"

dsl_1_if = "sis1"

dsl_2_if = "sis2"

dsl_1_gw = "45.123.223.65"

dsl_2_gw = "24.23.134.1"
scrub in  on {$dsl_1_if, $dsl_2_if} all fragment reassemble

scrub out on {$dsl_1_if, $dsl_2_if} all random-id fragment reassemble
block in on $int_if from any to any

block out on $int_if from any to any
block in on $dsl_1_if from any to any

block out on $dsl_1_if from any to any
block in on $dsl_2_if from any to any

block out on $dsl_2_if from any to any
pass in quick on $int_if from $lan_net to $int_if

pass in quick on $int_if from $lan_net to lo0
pass in on $int_if route-to { ($dsl_1_if $dsl_1_gw) } proto tcp from {

$users } to any port $bittorrent_tcp_ports flags S/SA modulate state

pass in on $int_if route-to { ($dsl_2_if $dsl_2_gw) } proto tcp from {

$users } to any flags S/SA modulate state
pass out on $dsl_1_if proto tcp from any to any flags S/SA modulate state

pass out on $dsl_1_if proto { udp, icmp } from any to any keep state

pass out on $dsl_2_if proto tcp from any to any flags S/SA modulate state

pass out on $dsl_2_if proto { udp, icmp } from any to any keep state
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On Thursday 27 March 2008 09:30:31 am Jon wrote:

quoted text
> With multiple gateways specified, how can one go about executing

> programs while explicitly specifying only a certain subnet be used by

> said program?

>

> Example:

> two DSL lines, have all bit torrent traffic go through the first

> interface to the first DSL line and all other traffic to the other.