Extension not found in windows

Hello,

I can't get drupal to detect php_apc.dll using this mod. I've added the following to php.ini

[PHP_APC]
extension=php_apc.dll
apc.rfc1867 = on

I'm using thread safe version, and vc6 not vc9 from http://downloads.php.net/pierre/

Drupal 7.12
PHP Version 5.3.10

The status report generates:

"The APC module needs the apc extension see: http://www.php.net/apc." Not available

Thanks for any help provided