ZF2 Class PDO not founf but PDO is enabled in php config

My zf2 application always worked fine but suddenly I started getting this error

Fatal error: Class 'PDO' not found in /home/doaminName/public_html/http://ift.tt/1F1z0aY on line 21

My PHP version is native (5.4) and here is the Configure Command from phpinfo. PDO is enabled with this line --enable-pdo=shared.

'./configure' '--enable-bcmath' '--enable-calendar' '--enable-exif' '--enable-ftp' '--enable-gd-native-ttf' '--enable-libxml' '--enable-mbstring' '--enable-pdo=shared' '--enable-soap' '--enable-sockets' '--enable-zip' '--prefix=/usr/local' '--with-bz2' '--with-curl=/opt/curlssl/' '--with-freetype-dir=/usr' '--with-gd' '--with-gettext' '--with-imap=/opt/php_with_imap_client/' '--with-imap-ssl=/usr' '--with-jpeg-dir=/usr' '--with-kerberos' '--with-libdir=lib64' '--with-libexpat-dir=/usr' '--with-libxml-dir=/opt/xml2' '--with-libxml-dir=/opt/xml2/' '--with-mcrypt=/opt/libmcrypt/' '--with-mysql=/usr' '--with-mysql-sock=/var/lib/mysql/mysql.sock' '--with-mysqli=/usr/bin/mysql_config' '--with-openssl=/usr' '--with-openssl-dir=/usr' '--with-pcre-regex=/opt/pcre' '--with-pdo-mysql=shared' '--with-pdo-sqlite=shared' '--with-pic' '--with-png-dir=/usr' '--with-tidy=/opt/tidy/' '--with-xmlrpc' '--with-xpm-dir=/usr' '--with-zlib' '--with-zlib-dir=/usr'

Any idea of where the problem is coming from?

via Chebli Mohamed