PHP warning in error_log

[eluser]yabune[/eluser]
My CI site looks ok but I'm getting all the time this error in the error_log file:

Code:

[02-Dec-2009 16:27:01] PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/local/lib/php/extensions/no-debug-non-zts-20060613/apc.so' - Cannot open "/usr/local/lib/php/extensions/no-debug-non-zts-20060613/apc.so" in Unknown on line 0

Is this normal?

Thanks!