This looks like an issue after all:
I found that "uname -a" would give me info on the version installed.
This is from SME 6.5rc, on the same machine as v7.0b5 gives the message:
[root@myserver]# uname -a
Linux myserver 2.4.20-37.7.legacy #1 Mon Sep 27 21:50:48 EDT 2004 i686 unknown
If some-one tells me where to get CentOS 4.1, I'll be happy to try that, if that is useful.