As far as I know it should see only the IP address which is connected to your router's end....correct me if I'm wrong?
below is the configuration from router..
cisco router#show run
Building configuration...
Current configuration : 14740 bytes
!
! Last configuration change at 12:30:48 EDT Wed Sep 13 2006
! NVRAM config last updated at 16:44:05 EDT Fri Sep 8 2006
!
version 12.3
service nagle
service tcp-keepalives-in
service tcp-keepalives-out
service timestamps debug datetime localtime
service timestamps log datetime msec localtime
!
hostname ciscorouter
!
boot-start-marker
boot-end-marker
!
logging buffered 4096 notifications
no logging console
enable secret
!
memory-size iomem 25
clock timezone EST -5
clock summer-time EDT recurring
no network-clock-participate slot 1
no network-clock-participate wic 0
no aaa new-model
ip subnet-zero
no ip source-route
ip tcp timestamp
ip tcp path-mtu-discovery
!
!
no ip domain lookup
!
no ip bootp server
ip cef
ip audit po max-events 100
!
!
!
!
!
!
!
!
!
!
!
!
interface FastEthernet0/0
description Physical Link to Base Switch Port
no ip address
ip access-group 143 in
ip access-group 110 out
no ip redirects
no ip unreachables
duplex auto
speed auto
!
interface FastEthernet0/0.10
bandwidth 1544
encapsulation dot1Q 10
ip address 12.32.x.x.255.255.128
ip access-group 143 in
ip access-group 110 out
no snmp trap link-status
!
interface FastEthernet0/0.30
bandwidth 1544
encapsulation dot1Q 30
ip address 12.31.x.x.255.255.248
ip access-group 143 in
ip access-group 110 out
no ip redirects
no ip unreachables
no snmp trap link-status
crypto map rtp
!
interface FastEthernet0/0.40
encapsulation dot1Q 40
ip address 12.31.x.x.255.255.248
ip access-group 143 in
ip access-group 110 out
ip verify unicast reverse-path
no ip redirects
no ip unreachables
no snmp trap link-status
crypto map rtp
!
interface Serial0/0
ip address 12.125.x.x.255.255.252
ip verify unicast reverse-path
no ip redirects
no ip unreachables
ip load-sharing per-packet
encapsulation ppp
no fair-queue
crypto map rtp
service-policy input mark_http_hacks
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/1
ip address 12.124.x.x.255.255.252
ip verify unicast reverse-path
no ip redirects
no ip unreachables
ip accounting output-packets
ip load-sharing per-packet
encapsulation ppp
no fair-queue
crypto map rtp
service-policy input mark_http_hacks
!
no ip http server
no ip http secure-server
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0/1
ip route 0.0.0.0 0.0.0.0 Serial0/0
ip route 12.171.2.x.x.255.0 12.31.48.83
!!
!
!
line con 0
line aux 0
line vty 0 4
exec-timeout 0 0
password
login
line vty 5 15
exec-timeout 0 0
password
login
!
end
