Reviewed the PHP5 firebird drivers.

1/ Indeed, the PHP5 driver registers both ibase_* and fbird_* versions
of all functions

2/ It does not do dual registration of the module name. Not sure yet if
that will work.

3/ The build code will link against fbclient if configure is given a
path to a FB install (broken on Windows, but the intent is there).

4/ The win32 build on www.php.net includes a version linked to
gds32.dll and this dll is included in the download

5/ Even the new and experimental PDO module, php_pdo_firebird.dll, is
linked against gds32.dll !!

Paul