It must be the thing to do. Just after Epicor said it was buying HR specialist Spectrum, a deal completed this week, Lawson Software said it will buy Enwisen, which markets SaaS-based HR products. Lawson is paying $70 million in cash and said the Enwisen HR Service Delivery Suite  will become the Lawson Human Capital Management (HCM) System. This is a higher-end system, with Enwisen reportedly having about 260 customers, with many of them in the Fortune 1000. But it looks like ERP vendors have concluded that bulking up on HR is necessary to compete in this market.