Minimal set of things that have to be done to comply with 3.8
1. Support SQL_OV_ODBC3_80 value for SQL_ATTR_ODBC_VERSION, returning SQL_ERROR for values other than SQL_OV_ODBC2, SQL_OV_ODBC3, and SQL_OV_ODBC3_80. iirc this is even done
2. Driver should return 03.80 from SQLGetInfo for SQL_DRIVER_ODBC_VER info type
3. SQLGEtInfor should return SQL_ASYNC_DBC_NOT_CAPABLE for SQL_ASYNC_DBC_FUNCTIONS info type, i.e. asynchronous operations are not implemented.
4. Support of SQL_ATTR_RESET_CONNECTION connection attribute
5. Streamed output parameters emulation
6 SQLCancelHandle support. iirc this is even done

After re-reading of docs, I've decided, that output parameter streaming is not mandatory. Other items have been added, tests changed/added.
4.0 goes to the separate ticket.