I have installed \'WampServer2.1e-x32\' stack with addon version of php 5.2.11 . I downloaded apc3.0.19.dll and placed under the directory and required information in php.in
A bit late for user269867, but I found a solution (APC 3.1.9 / 3.1.13) :
You can also follow this :
https://bugs.php.net/bug.php?id=59445
Where it is said :
"If compiling is not an option, roll back to stable: pecl install -f APC-3.1.6"
It is indeed a regression, but it worked fine for me :)
(I also responded that in APC (Alternate PHP Cache) Throwing Lots of PHP Notices)