More information on the vulnerabilities of the DIEBOLD machines:
Time to Recall E-Vote Machines?
The problems are not just in the cyber-security, but in the phyiscal as well:
excerpt:
Officials leave voting machines at polling stations days before the election. The machines contain memory cards with ballots already loaded on them. This means before the election, someone could alter the ballot file in such a way that voters would cast votes for the wrong candidate without knowing it.
The memory card rests behind a locked door on the side of the voting machine. But supervisors receive a key to the compartment the weekend before the election. The same key fits every machine at a polling station.
Poll supervisors are selected with no background checks and are given keys to buildings where they can access the machines several days before the election.
The machines, worth around $3,000 each, are locked on a trolley at polling stations with only a bicycle lock. The combination, which anyone could crack in a couple of tries, is the same for every polling station in the county and is given to poll supervisors during their training.
Although the machines have two blue tamper-resistant ties threaded through holes in their carrying cases, the ties can easily be purchased on the Internet. Supervisors open at least one case the night before the election to charge the machine inside, which means the case remains unsealed overnight.