[rules-users] recommend way about same when , different then

Hi. I'm newbie to Drools. I'm just wondering how I define the rules with my web application that has several layers, web,business-logic,and data access. one rule is used in the wab layer, and another one is used in the business-logic layer. Both rule's "when" are the same, but the "then"(action) is different. It looks like code dupulication. (I mean when the "when" changes, every rules that has same "when" has to be changed, right?) What's the recommended way in this situation? thanks Shige