Question : Problem: MegaPath Partial T-1

've just purchased a partial T-1 from MegaPath and would like to configure my Cisco 2600 for it (as opposed to buying their $800 Netopia router).  I just installed a T1 CSU/DSU unit in the router.  Unfortunately, they don't support my router.  Here is the information my ISP has given me:

Cisco WAN IP: 69.33.108.186 to 69.33.108.190
Gateway: 69.33.108.185

DNS: 64.7.11.2, 66.80.131.5

encapsulation frame-relay IETF
frame-relay lmi-type ansi
dlci 16

This is how I've configured my router:

Building configuration...

Current configuration : 1555 bytes
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
service password-encryption
!
hostname Internet
!
enable secret 5 $1$5lRn$iWmuHbQKZOFzzlTRJSulV.
!
!
!
!
!
ip subnet-zero
ip name-server 64.7.11.2
!
!
!
!
interface Ethernet0/0
 description connected to EthernetLAN
 ip address 120.0.0.150 255.255.255.0
 ip nat inside
!
interface Serial0/0
 no ip address
 ip nat outside
 encapsulation frame-relay IETF
 no ip mroute-cache
 frame-relay lmi-type ansi
!
interface Serial0/0.1 point-to-point
 description connected to Internet
 bandwidth 768
 ip address 69.33.108.186 255.255.255.248
 ip nat outside
 no arp frame-relay
 frame-relay interface-dlci 16
!
router rip
 version 2
 passive-interface Serial0/0.1
 network 120.0.0.0
 no auto-summary
!
ip nat inside source list 1 interface Serial0/0.1 overload
ip nat inside source static 120.0.0.4 69.33.108.187
ip nat inside source static tcp 120.0.0.4 1433 69.33.108.187 1433 extendable
ip nat inside source static 120.0.0.155 69.33.108.188
ip nat inside source static tcp 120.0.0.62 5631 69.33.108.189 5631 extendable
ip nat inside source static udp 120.0.0.62 5632 69.33.108.189 extendable
ip classless
ip route 0.0.0.0 0.0.0.0 Serial0/0.1
no ip http server
!
access-list 1 permit 120.0.0.0 0.0.0.255
snmp-server community public RO
!
line con 0
 exec-timeout 0 0
 password 7 0502081C28424D
 login
line aux 0
 password 7 03165E0F0703245E5A
 login
line vty 0 4
 password 7 0833494A0815000506
 login
!
end


After using the following config and issuing a "no shutdown" command, both the serial interface and the line protocol was still down.  I spoke to the ISP and they told me there was something wrong with CSU/DSU, so I've returned it for another one.  In the meanwhile, does this configuration look correct?  The only other thing I could think of was that they mentioned that the interface needed to be set for 12 channels, as it is a partial T1.  I don't know anything about this?  Can someone shed some light?  

Thanks!

Answer : Problem: MegaPath Partial T-1

You may need to upgrade your 2600 to 12. 2(15)ZL or better. Suggest 12.3
You have 12.1(8).
Support in the 1700 started with ver 11.2
Support for 2600 started with ver 12.2(15)ZL