Sftp access files of mac from internet.

Hi all,

Here is the situation, I've enabled remote login in system preferences which also activates sftp as well as ssh. i've forwarded port 22 to my imac, and created a dynamic dns entry to my public ip address.
Now when i login to another unix box on the net, i can ssh and sftp to the mac with no problem via terminal (command line)

Now the problem is that i want to be able to connect to the sftp/ssh from my pc using secure crt for ssh and any ftp program that uses sftp as a protocol. however it dosent make the connection for some reason. It just hangs

setting for sftp are as follows, still does not connect (if i enable ftp i can connect with no problem)
protocol sftp
my public ip address
port 22
user and pass



setting for ssh in secure crt
ssh2
public ip address
pot 22
username/password

cipher 3des
mac: md5
Authenication: password
ssh server: standard

It just hangs and won't connect. No firewall enabled Is there anything i'm missing ?

Luke