Errors with SYSMAIN

I made a program that works with Sysmain, passing objects from one to another library, if the program was cataloged without xref it tried to catall it. It worked ok with version 3.1 and olders, but, now with 4.1 it cancels with next error:
Error: 935 occurred in SMPERRTA (SYSMAIN error transaction),
line 165
Processing has abnormally terminated.

Basically, the program puts all comands necessaries in the stack. I can send the source of the program that cancels to anybody can examine it.
If anybody speaks spanish, better!!!
Thanks, Fabi

Did you copy the SYS* modules from FNAT to FUSER? If so, is it possible that you are using outdated 3.1 modules in a 4.1 environment?

Check the SYS* modules on SYSTEM (FUSER) or any of your steplibs including your current library, if necessary, and compare the directory entries of that modules to the directory entries on SYSTEM (FNAT).