haproxy work on my local lan but not from the itnternet

Hi all

I have a very simple setup, I have a ubuntu server running haproxy_1.3.12.dfsg-1_i386.deb. This is a internal server not my firewall and does dispatch the traffic.

internet -- fw nat box ----- haproxy ----- tcp server 1 ---- tcp server 2

If I take a client on my internal network and connect to my haproxy everything works great and is balance to my 2 servers

If I take a client on the internet traverse my firewall and go onto the haproxy the tcp packet is ack by haproxy and nothing more

Here is my haproxy.cfg file

global

        log 127.0.0.1 local0 debug
        maxconn 4096
        user haproxy
        group haproxy

defaults
        log     global
        mode    tcp
        option tcplog
        retries 3
        maxconn 2000
        contimeout      5000
        clitimeout      14400000
        srvtimeout      14400000

listen rdpfarm :3389
       mode tcp
       balance source
       server RDP-1 192.168.4.111:3389 check
       server RDP-2 192.168.4.201:3389 check

Any clue would be very appreciated

-- 
Guillaume Bourque, B.Sc.,
consultant, infrastructures technologiques
Logisoft Technologies inc.
514 576-7638
http://www.logisoftech.com