Since the default to UsePrivilegedPort has been changed to "no",
RhostsRSAAuthentication does not work for older servers
(including that in potato).  It may be a good thing to add
a notice to /etc/ssh/ssh_config about this info.
--- ssh_config.orig	Mon Mar 26 15:43:04 2001
+++ ssh_config	Mon Mar 26 15:52:15 2001
@@ -26,12 +26,15 @@
     ForwardX11 yes

 # Site-wide defaults for various options
+### Note that you need to set UsePrivilegedPort to "yes" to use
+### RhostsRSAAuth with older sshd servers.  See manual ssh(1).

 # Host *
 #   ForwardAgent no
 #   ForwardX11 no
 #   RhostsAuthentication no
 #   RhostsRSAAuthentication yes
+#   UsePrivilegedPort no
 #   RSAAuthentication yes
 #   PasswordAuthentication yes
 #   FallBackToRsh no