Looks like it is informix-specific:
from Informix odbc driver Programmers Manual
"Instead of accessing smart large objects using the ifx_lo functions, you can
access smart large objects using the standard ODBC API.
Operations supported when accessing smart large objects using the standard
ODBC API include select, insert, update, and delete for CLOB and BLOB data
types. You cannot access BYTE and TEXT smart large objects in this way."
the fields it's complaining on are indeed BYTE types