In the wake of high-profile compromises of companies such as Facebook, the New York Times, Apple and others, officials at Zendesk, an online customer support provider, said that the company also had been compromised and the attackers had made off with the email addresses of customers of Twitter, Tumblr and Pinterest, all of which use Zendesk's services.All three companies sent out emails to affected customers, notifying them of the incident and warning that their email addresses may have been compromised. In what has become an almost daily occurrence now, Zendesk officials posted a notice on the company's blog with the heading "We've been hacked"