Arum Kumar had never shaken hands with a foreigner nor needed to wear a necktie. He vaguely thought that raising a toast had something to do with eating bread. But Mr. Kumar, 27, and six other engineers were recently recruited by the Hyderabad offices of Sierra Atlantic, a software company based in Fremont, Calif. And before they came face-to-face with American customers, the new employees went through a challenging four-week training session aimed at providing them with global-employee skills like learning how to speak on a conference call and how to address colleagues.