BROOKFIELD, Wis. – Checking out Check 21 has apparently been onthe minds of a lot of financial institution executives, judging bythe attendance at a series of seminars Fiserv has been holding onthe topic. More than 1,900 managers have attended the sessions sofar in a nationwide series that will conclude in May, the companysaid. Check 21 goes into effect on Oct 28 and will require creditunions and banks to accept substitute check images, as well astrain their staff in the processing and re-credit implications ofthe law and notify consumers of the change, said Mark Damico,president of the Fiserv Item Processing Group. Fiserv is thenation's third-largest processor of checks, with 67 centers in theUnited States and Canada. The final of the series of 41 seminarswill be on April 7 in Richmond, Va., April 8 in Indianapolis; April20 in Brookfield and May 12 in Minneapolis, the company said.