Brookline (Mass.) Retirement System began a review of its $155 million pension plan, said Margaret M. Cossette, acting director. It may be completed by Sept. 24; manager changes are not expected, she said. The plan hasnt been reviewed since Meketa Investment Group replaced Wilshire Associates as consultant in January. The asset allocation is 50% domestic equity, 40% fixed income and 10% international equity. Meketa is advising.