PHP Fatal error

Hi all,

I am facing a problem while trying to open a php which is configured with ldap.

The problem is when i try to open that php thru ie it gives me a blank page
when i see the apache error_log there is a on line description of the error saying"Call to undefined function ldap_connect() in /usr/local/apache2/mediawiki/up/index.php"

My php version is php-5.0.1
and my apache version is apache2.0.48

Configuration with mysql apache and ladap was succesfull by using the comand
./configure --with--apxs2 --with--mysql --with--ldap

Please help me in resolving the above mentioned issue.

Thanks in advance,
Eswar.