Ubuntu11 putty not working

[Roger]

Using Ubuntu 11 and putty on a desktop installation and a test bed 
ubuntu11 server installation on separate hard drives.
puTTY does not display the login, username or password request, just the 
black puTTY window with a static  green cursor, it will not accept 
keyboard input.

I suspect there may be a file missing but have no idea what to look for.
Has anyone had this and how is it solved.
Alternatively is there a puTTY alternative for ubuntu 11

Using Fedora 14 and puTTY it shows login and requests user and password 
and grants server access.

help would be appreciated, thanks
Roger