__       
    ___/  \_                                                2.2.2.2         \
  _/        \__                                            +--------------+  \
 /     DMZ     \           +-------------------------      | Connection 1 |   \
| 192.168.0.253 |----|     |                   eth2 +------+--------------+    \
 \255.255.255.0/     |     |          L     default |       3.3.3.3             \
   \__     __/       |     |          I             |      +--------------+      \
      \___/          |-----+ eth0     N        eth3 +------| Connection 2 |       \
                           |          U R           |      +--------------+        \
                           |          X O           |       4.4.4.4                 +---INTERNET
        __                 |            U           |      +--------------+        /
    ___/  \_         |-----+ eth1       T      eth4 +------| Connection 3 |       /
  _/ LOCAL  \__      |     |            E           |      +--------------+      /
 /     NET     \     |     |            R           |       5.5.5.5             /
|   10.0.0.0    |----|     |                   eth5 +------+--------------+    /
 \_255.255.0.0_/           +-------------------------      | Connection 4 |   /
   \__     __/                                             +--------------+  /
      \___/                                                                 /

Our setup is as show above....

We have a linux router with default route through eth2 with ip 2.2.2.2
Router does ip_forwarding.
Router has four connections, three with public ips (eth2 ,eth3, eth4)

DMZ is in subnet 192.168.253.0/24
LOCALNET is in subnet 10.0.0.0/8 which is further broken down into subnets of 
10.0.0.0/16
10.1.0.0/16
10.2.0.0/16
10.3.0.0/16
10.4.0.0/16
10.5.0.0/16

DMZ subnet when initiating new connections to the internet will go through the linux router and out through eth2 because eth2 is default route for the router. This is fine.
I want to route based on source originating in the localnet so as to break up the subnets and make use of all the internet connections we have.

I want all connections originating form the 10.0.0.0/16 block and 10.4.0.0/16 block to go out through eth2 of router. (This should be default so i dont think requires any additional configuration. please correct me if i am wrong)
I want all connections originating form the 10.1.0.0/16 block to go out through eth3 of router
I want all connections originating form the 10.2.0.0/16 block and 10.3.0.0/16 block to go out through eth4 of router
I want all connections originating form the 10.5.0.0/16 block to go out through eth4 of router

Nat-ting will obviously be involved...
I am using firewall builder to build these rules...
can i mange to do all of this usinf fwbuilder?
Please help...