Verint Systems is buying Kana Software, a portfolio company of Accel-KKR, for $450 million. The private equity firm paid $48.9 million cash for Kana in 2009 so investors have done well. Kana specializes in customer service products, including self-service tools such as chat and web self-service, along with social media monitoring. Verint markets what it calls Actionable Intelligence solutions to capture and analyze customer transactions.