An Open Data Services gateway to Rdb might use a resource file named ODSRDB.DLL. Also, this gateway might be able to interpret the Transact-SQL USE command to set the default schema for a user differently from the default used by the gateway instance. The ODBC.INI file might look like this for a data source pointing to this gateway:
[RdbGate] Driver=C:\WIN31\SYSTEM\odsgate.dll Description=SQL Server gateway for Rdb OemToAnsi=No GatewayResource=c:\win31\system\odsrdb.dll Initialization=USE sys$sysdevice:[user.fred]personnel