ssh problem

I have server in remote place and wanted to connect to that server
(Fedora Core 4)by ssh through internet. I am able to ping that server
from my local system (Redhat Linux box) when i am trying to connect
through it is giving error "connection closed". I checked all firewalls
and iptables there is no restriction for the port to block. And one
more intresting I tried to login from the server system (fedora core 4)
to itself through ssh it is giving same error "connection closed" . So
please help me to overcome from this problem.

Thanking u all in advance.


Regards,
Praveen