Judge Certifies Great Western Suit: A federal judge certified a class-action lawsuit charging that Great Western Bank tricked elderly, unsophisticated depositors into moving their savings from federally insured savings accounts into bank-sponsored uninsured mutual funds. In a lawsuit filed in April, nine depositors claimed Great Western employees conspired to gull them into buying mutual funds managed by Sierra Advisors Inc.--the bank's sister unit--by failing to explain that the funds were risky, weren't federally insured and charged commissions. U.S. District Judge Irving Hill certified the class action to include as plaintiffs all California resident customers of Great Western Bank branches in 14 Southern California counties who, between April 13, 1992, and April 13, 1995, bought securities from one of Great Western's securities brokerage units. Similar actions have been filed in state courts. Great Western denies any wrongdoing and says it informed its customers fully.