bcp_bind with NVARCHAR with FreeTDS 1.00.15

I'm have issues using the programmatic bcp APIs and a table with an
NVARCHAR column.

If I specify a data type of NVARCHAR (0xe7) to bcp_bind's db_vartype
parameter, bcp_sendrow fails in tds_convert since there is no conversion
for the NVARCHAR type supported by tds_convert. This fails with an error of
"Requested data conversion does not exist", though this error is generated
internally from FreeTDS.

If I specify VARCHAR as the data type, the server rejects the input data
with an error of
"Unicode data is odd byte size for column 4. Should be even byte size."

Any ideas?