starts a backup on both logins at same time!

[shaneblyth]

I set up a backup schedule.
Superduper doesn't need to be running - it will automatically start itself at the due schedule time.

My problem - It starts itself on 2 different users !
I've only ever set it up on my login - which it starts its scheduled backup on.
But - it also loads itself to do the scheduled backup on the other login - which then fails (as it's already in progress on my login).

Any ideas on what I have done wrong or how I should set this up so it doesnt do it?

Latest superduper and snow leopard on a mac mini

thanks