The 1.2 Plugin update of OCCP for WooCommerce fixes compatibility with WooCommerce 2.1 and adds jQuery based numeric digits only support for the Card Number and Card CSC fields at Checkout.
Here’s the full changelog:
* Added: Limit Card Number and CSC to numeric digits
* Changed: Dropped $woo_oc global
* Added: Using Plugin constants
* Added: Maxlength of CSC field depending on card type
* Fixed: No Checkout screen on WooCommerce 2.1