lock table & update cursors problems

Hi, We have a 4gl program that updates, inserts & deletes more than a million of records in 3 tables, and all the tables in our system have "lock mode row". Our server has 600.000 locks and the memory is scarce so we can't increase that number. The first thing we do after the "begin work" is lock the three tables in "share" mode. Then, we declare the update cursors and start the processing. But the onmode -k shows an increasing number of locks and the process fails with a "no more locks" error. The process is run with no other users logged. Seems that the "update cursor" uses a lock for each row without considering the "lock table" statement. Is this the standard behavior of the engine? We are using Informix Dynamic Server Version 7.31.UC2 on a SCO Release = 3.2v5.0.4 Thanks in advance for your help -- Manuel A. Daponte Santiago Systems Consultant, ICP