cvs over ssh with non standard port

[Micha Feigin <michf@post.tau.ac.il>]

I am trying to get cvs to access the repository through a ssh connection
when the sshd is listening on a non standard port.
I tried using
cvs -s CVS_RSH="ssh -p port" -d :ext:cvs:/var/lib/cvs co package
but cvs insisted on trying port 22.
Is it possible to do this?