Pennsylvania State Association of Boroughs Municipal Retirement Trust, Harrisburg, hired four active equity managers: Aeltus, $15 million, enhanced core; Armstrong Shaw, $15 million, large-cap value domestic; J.L. Kaplan, $15 million, small-cap value domestic; Lazard, $5 million, international. All four managers replace C.S. McKee. The $110 million plan made the switch for diversity and because of McKees performance, said Gary Crisci, senior financial consultant at consultant Merrill Lynch. A spokeswoman for C.S. McKee did not return calls.