Porting from SCO 3.2.4 to SCO ODT 5.0.4

Hi, I have a problem porting an application compiled for SCO 3.2.4 to SCO ODT 5.0.4 The system is a PC running Informix SE 5.0 and 4gl 4.1 "C" runtime. I have copied the informix se and 4gl rt files over to ODT and the database seems to work fine - dbaccess works and is able to successfully query the db. When I copy the 4gl binary over, it works until the second iteration of a fetch .. update loop and then crashes with a coredump. The corefile just says that there was a bad memcpy at an address. No trace information. Is ODT binary compatible with SCO? ODT seems to use ELF format binarys while SCO uses COFF. If this isn't a binary compibility problem, then maybe it's to do with the ISAM version of SE - the database interfaces with a C-ISAM system. Does anyone know what C-ISAM versions are in each release of SE? Thanks, Ciaran Kelly