[SlugBug] ssh keys fubar'ed

[Bill Best]

hi

i run an rsync backup job over ssh under cron and i did the trick about 
exchanging public keys to get around the password problem - as helpfully 
described by o'reilly here:  http://hacks.oreilly.com/pub/h/66

anyway, all was running well but i have since moved one of the servers 
to a co-lo facility and given it a new hostname and so on.

now ssh/scp doesn't work.

how do i get rid of all the old keys and start all over again?

many thanks in advance.

bill