By default Shopp will authorize only on payments. The merchant can manually capture payment when products ship. This is confirm the rules set by Visa and Mastercard.
When merchants want to auto capture payment right away they can add a filter to their theme’s functions.php. To prevent merchants from having to get their hands dirty on coding we created a simple plugin that will do the same thing.
One more benefit, you will not lose the functionality on theme updates or theme change.
Download from WordPress.org.