You cannot build PHP with multiple ODBC drivers or driver managers e.g. you cannot use any two of the configure options from the list below (current of PHP4b3):
If you want to access multiple ODBC drivers from PHP the best method is to install the unixODBC driver manager and then tell the unixODBC driver manager about your ODBC drivers.
You can build PHP with an ODBC driver and other database drivers such as Oracle® or MySQL as these drivers do not provide the same ODBC API.
Oracle is a registered trademark of Oracle Corporation and/or its affiliates.