Don't send "exec" command on login

[Rolando Pereira]

Hello,

I need to connect to a server X that I can only connect after connecting 
to another server Y first.

As I understand from reading the documentation, I can do multi-hops 
using proxies. The problem is that the Y server has a weird shell that 
only accepts the following commands:
ssh, telnet, who, last, passwd, help, version, quit, exit, and logout

So when tramp trys to run tramp-open-connection-setup-interactive-shell 
and send the string "exec env ENV='' PROMPT_COMMAND='' PS1='$ ' PS2='' 
PS3='' %s" it hangs.

If I try to change that string to "ssh X", it works, but since the shell 
at Y can't add the server key to the known_hosts file, I have to type 
and addicional "yes" (because of the "Are you sure you want to continue 
connecting (yes/no)?") plus send the password again.

I tried to place two tramp-send-command at 
tramp-open-connection-setup-interactive-shell, one for "ssh X" and 
another for "yes", but that doesn't seem to work (it only runs the "ssh 
X" and it seems that it doesn't run the second command).

Is there any way to connect to the server X? I think that since 
multi-hops uses the tramp-open-connection-setup-interactive-shell they 
are not the answer in this case. Am I wrong?