title: Drools - multiple activation group
body: <p>I have written a Drool rule as shown below:</p>
  
  <pre><code>rule "first and second"
          activation-group "first"
          activation-group "second"
      when
          // conditions
      then
          // actions
  end
  </code></pre>
  
  <p>However, when compiling, I get this error:</p>
  
  <pre><code>Duplicate attribute definition: activation-group in rule first and second
  </code></pre>
  
  <p>I want to know if it is possible to include multiple <code>activation-groups</code> in a rule. If this is possible, how can you do it?
  Thanks in advance.</p>