"pdo_mysql.so ? duplicate?

Hi All
i face some problem in in my site.
what it means all my site which is under cpanel/whm have get huge size of error_log.
after we find the error_log file the same line is repaed
like

HTML:

[05-Nov-2011 22:54:34] PHP Warning:  Module 'pdo_sqlite' already loaded in Unknown on line 0
[05-Nov-2011 22:54:34] PHP Warning:  Module 'SQLite' already loaded in Unknown on line 0
[05-Nov-2011 22:54:34] PHP Warning:  Module 'pdo_mysql' already loaded in Unknown on line 0
[05-Nov-2011 23:09:23] PHP Fatal error:  Allowed memory size of 134217728 bytes exhausted (tried to allocate 35 bytes) in /disk2/asedt/public_html/subdomain/libraries/joomla/filesystem/folder.php on line 408

i find php.ini file that extension . that line is below

HTML:

extension = "pdo.so"
extension = "pdo_sqlite.so"
extension = "sqlite.so"
extension = "pdo_mysql.so"
extension = "pdo.so"
extension = "pdo_sqlite.so"
extension = "sqlite.so"
extension = "pdo_mysql.so"
extension = "pdo.so"
extension = "pdo_sqlite.so"
extension = "sqlite.so"
extension = "pdo_mysql.so"
extension = "pdo.so"
extension = "pdo_sqlite.so"
extension = "sqlite.so"
extension = "pdo_mysql.so"

which line i need remove . please guide me. all that site have face memory limit error. but i increase php memory value 64 to 128. but no improvement kindly help me