keep connection open?

[Tom_Roche]

It appears that tramp closes its ssh connection to a given host when
the last buffer connected with that host is killed. If I subsequently
open another file on that host, I must then wait through the login,
etc. 

Is there a way to instead make tramp leave the connection open until I
close _emacs_, even when no buffers are open to that host?

TIA, [EMAIL PROTECTED]