TGT forwarding when cross-realm auth?

[vadim <vadim.tarassov@swissonline.ch>]

Hallo everybody,

First time in my life I managed to establish trust between two realms,
realm A and realm B. Trust is one-way, where B trusts A. 

Now when I do ssh from unix box from realm A to unix box in realm B, my
TGT from realm A gets forwarded to box in realm B. My principal remains
me@A.

This is however not the functionality I am looking for. Instead of
forwarding krbtgt/A@A, I would like to get krbtgt/B@B in my credential
cache on unix box in realm B once ssh'ed in it from unix box in realm A.
And I would my principal to become me@B instead of me@A.

Reason one I am looking for such functionality is 

1) we (realm A) do not trust realm B and do not want credentials from
realm A to be saved on that filesystem.

2) we however still want users to login from A to B without entering
passwords.

Could you please tell me how I could get such functionality?

thanx a lot and best regards, vadim tarassov.

-- 
vadim <vadim.tarassov@swissonline.ch>