exchange server connection problem

Strange behaviour: using same script with php.exe and php-win.exe (cli) give different result in connecting to an exchange server. Using phpmailer class it is generated a "$Language string failed to load: connect_host" error. I tried using mail() php function and problem still exist, so this is not a phpmailer class problem. I've assured using same php.ini, tried to ini_set() relevant settings in script, but php.exe connects and php-win.exe doesn't. Any clues?? Thanks. Davide