packet/session passwords

I have a uplink that /just/ has a packet password set for me, no session 
password. If I use that packet password /only/ I can't connect with him.

If I use that password in the session password option, I can connect with 
him. 

Why do I have to use his packet password in my session password option to 
connect with him? Makes no sense to me.

        Kevin

--- GED3 2.5+ 5005