I have a CQ5 developer trial version setup on a local system. When I tried to follow the directions given in http://helpx.adobe.com/adobe-cq/using/creating-custom-cq-commerce-providers.html, to create custom CQ commerce providers, got errors with many classes like com.adobe.cq.commerce.api.promotion.Voucher and com.adobe.cq.commerce.common.AbstractJcrCommerceService - that these classes do not exist. Other classes like com.adobe.cq.commerce.api.Product do exist in the class path. I tried adding all available jars in the classpath but still got errors for some of the above mentioned classes.
Is there a limitation on the edition that we can't use these classes? Is the developer edition a stripped down version of the production version?
If version you are using is 5.5 Make sure you installed the ecommerce package.