4GL error in Linux

Hello, I've installed the SE-esql/C 7.24.uc5 bundle in Red.Hat Linux 5.2 to use the D4GL programs that my company has been selling for SCO and AIX. I've installed the 4JS compiler version 2.02.3b1. All the programs work well except for one program that systematically crashes. It doesn't position correctly within a cursor. I get the message: SQL statement error -244 could not do a physical-order read to fetch next row system error number -35 operation would block It only happens when two users try to access the same set of tables/rows at the same time. It happens with different statements (update, delete,...) When running the same program in SCO it just hangs with an error in the most peculiar places. None of other several programs have this kind of behavior. In all of them we have a SET LOCK MODE TO WAIT in the main 4GL program and only in this program it crashes. Can anybody help me ? Thanks in advance,.. David