When handling RPC parameters of datatype tinyint,
only valid values (between 0 and 255) can be passed back. If the
back-end database returns a negative value, that value is passed
to the user as a NULL value.
Sybase recommends that you use smallint datatype because it can handle negative
numbers correctly. Oracle stored procedures with long and
long raw datatypes are not supported with output parameters.
Also, long raw input parameters are not supported.