ssh from outside to home ubuntu failed

[smouser]

I have set up portforwarding with my buffalo air station and have set up ssh in my ubuntu. I was able to connect to my ubuntu from outside but now i fail. Not sure what has been changed/wrong
1. port forwarding is setup, from router Internet IP to local lan IP, e.g.
Internet:22 --> 192.168.11.2:22

2. Firewall disable for port 22

3. Ssh from within works, so sshd is configured correctly
[martin<> localhost ~]$ ssh 192.168.11.2
The authenticity of host '192.168.11.2 (192.168.11.2)' can't be established.
RSA key fingerprint is 47:29:03:3f:b5:87:90:1b:58:67:52:82:f4:6a:7c:9d.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added '192.168.11.2' (RSA) to the list of known hosts.
Password:
Last login: Sat Feb 4 10:24:49 2012 from localhost.localdomain
[martin<>localhost ~]$ telnet 192.168.11.2 22
Trying 192.168.11.2...
Connected to 192.168.11.2.
Escape character is '^]'.
SSH-2.0-OpenSSH_5.5

Protocol mismatch.
Connection closed by foreign host.
(all at sign replaced by <>)

anything else i should check?

[smouser]

Correction: Internet:22 --> 192.168.11.2:22 , Internet means my router internet address

[smouser]

And connect to the internet address from inside failed
[martin<>localhost ~]$ ssh <Internet address>
ssh: connect to host <Internet address> port 22: Connection refused

[smouser]

More info, there is no IP restriction on my own sshd, in /etc/ssh/sshd_config

Port 22
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress 192.168.1.6
#ListenAddress ::


Also, no firewall set in my router to block port 22
Screenshot-AirStation Settings - Mozilla Firefox.jpg

[Rubberman]

Do you have a static IP address from your ISP, or is it dynamic? If dynamic, then that is your problem since you cannot know externally what the actual IP address of your router is. In any case, even though you may have the same dhcp address for some period of time, that can change at any time when the lease expires.