how delete unknown master password?

On a mac at work, former co-worker was using smartsvn. Master password is not known. Tried uninstalling smartsvn, and re-installing. But somewhere it still stores master password, so can't remember new svn repository passwords. Was able to delete the old svn URLs, so can enter username/password each time. But that is not practical long term. Need to get smartsvn completely uninstalled, or find what to delete to be able to start over, with new master password.