[OS X Emacs] Tramp problem: need password to save in remote file?

[stefanos folias]

recently i installed OS 10.5 and downloaded and installed the latest  
Aquamacs emacs.

since that time i have noticed that when i am remotely editing a file  
via Tramp, everytime i save to the file it requires my password,  
similarly if i access another file.

i am confused why this is occurring since i should actually be logged  
in  via ssh to the server where the remote file sits.

i have the following lines in my .emacs file

(setq tramp-default-method "ssh")
(require 'ssh)


i never had this problem using tiger.  does anyone know what's causing  
this?  is it leopard, is there something i need to change?

any advice would be greatly appreciated.

thanks

stefanos