The recent marriage of Bank ofAmerica and FleetBoston shows thatthe urge to merge may be back. But consumersshould be vigilant. Often, whenbanks merge, routine services like automaticbill payments can get fouled up. Ifthat happens with a credit card payment,you could be slapped with a late chargeand have your interest rate ratcheted upto 25% or even higher. If your bank isinvolved in a merger, your first move is tomake sure that its bill-paying systems areworking properly. If you do get hit with alate penalty because the bank botchedthe payment, call the credit card issuer.Most companies will forgive the first latefee, especially for customers with a longhistory of timely payments.