phpize calendar

Is it possible to phpize the calendar module?  I've downloaded the  
5.2.6 source, cd into ext/calendar, and run the following commands:

phpize
make
sudo make install

I then went into the php.ini file and added extension=calendar.so

I also commented out the extension_dir directive, as well as setting  
it to the full path of where the calendar.so is located '/usr/lib/php/ 
extensions/no-debug-non-zts-20060613'

I am running this on a Mac OS X Server 10.5.5 with Apache2 running.

Is there something I am missing?

Thanks,
Robert Everson