Hi Dave!
According the "Using the Application Program Interface" manual error 610
means:

0610 E DSM_RC_NLS_CANT_OPEN_TXT
Explanation:  The system is unable to open the message txt file
(dscameng.txt or dsmclient.cat for AIX). On the AS/400 plat-form this file
is QANSAPI/QAANSAMENG(TXT).
System Action:  The system returns to the calling procedure.
User Response:  Verify that the dscameng.txt file is in the directory
pointed to by DSMI_DIR. For AIX, verify that the dsmclient.cat file has a
symbolic link to /usr/lib/nls/msg/<locale>/dsmclient.cat .

Maybe this helps?
Kindest regards,
Eric van Loon