If you will be using ODBC to make any connections to databases, you should install UnixODBC (our preferred choice for the ODBC driver) now, per the instructions in InstallNotes-Database.txt. Any currently installed version of unixODBC should work with the latest Apache but having the latest version will ensure that all known bugs are fixed. Whatever you decide, you will need to know the name of the UnixODBC install directory during the PHP install step, if you want to use ODBC.