PHP Startup: Unable to load dynamic library

I am repeating the comment (which some might miss) by Nenhum Pois é above, because it is the real solution to the problem:

The problem was the fbclient.dll from the FB 64 bits installation. I just got the fbclient.dll from 32bits, copy it into the PHP root and it solved the problem

Cli and Apache PHP run with two different configuration files. That will explain the lacking error message in CLI mode. The likelihood is the extensions for this application where not stored in the PHP extension folder. I'm not versed with the configurations under windows so you may need to google for the Windows PHP extension directory and ensure your extension file is there.

Judging by your error the path is "C:\Program files(x86)\PHP\ext\

Please ensure your extension files are there before attempting to load them.