NAT should be Open

guys seriously need ur help @ opinion

My Modem is Riger DB108W  streamyx wireless

i just bought COD:MW2 R1 last 3 days, till today i cant even play single game online... it keep stuck at Matchmaking, even faintrulez and  thugs207 invite me also same, cannot play.. keep stuck..

here i summarized what i've done

1) Wired connection from modem to PS3 , internet ok , with 1.2mb download , 300kb upload

2) psn is good, can login very fast..

3) i cannot play Special Ops : Two player Online, when click it say s "Error Creating session"

4) everytime click Play Online or Friend invite it keep stuck at Matchmaking for several hours

5) Already deleted patch and download new 1 , save game also deleted still cannot play online

6) Port forward MW2  already done , DMZ setting ip manual for ps3 .. my NAT type is 2

7) Friend at Lobby : joinning session also stuck.. T_T
the game just bought (mint not 2nd hand) i can play offline (campaign) but problem when playing online.. my modem is Riger DB-108W

anyone can guide me ?.. is it i need to do any registation for my COD:MW2 before playing online or how?

=======================PROBLEMS SOLVED!!===========================

BIG THANKS TO FAINTRULEZ AND OTHER LYN FOR HELPING ME!!  

their solution is :

1) disable UPnP (universal Plug n Play) setting in RIGER DB 108-WL under Advance Tab / LAN
2) set DMZ at Riger Modem Setting for PS3 to that manual ip (for me i put 192.168.1.100)
3) use manual setting for PS3 connection ( whether is wired or wireless anything)
4) disable UPnP setting in PS3 (manual setting)
5) (optional)  MTU setting i tried 1486 for game and 1492 for modem
6) (optional) forward all ports for COD:MW2 at riger modem can be found at www.portforward.com

once or NAT type 2 (Open) u can started play online already

after 3 days and 6 hours of settings, finally i can online
thank you to all especially faint rulezz (i would kiss u if u're here)
u solve my problem + save my money for buying other modem .. thankss      

u add these few guys, all old-timer and they can help u practice.. 

leepast
winterblood
bestdo
choontoy
faintrulez
LuckyMonkeyFeet
ahmok69
prebet_lapok
davidgary73
gaox8322
Rinoa-lover

i also just join MW2 online community..
come2 add me too.. DrLaboo