d0ddde
@@ -1002,6 +1002,10 @@
public class MulticastProcessor extends ServiceSupport implements AsyncProcessor
         Map<Object, AggregationStrategy> map = CastUtils.cast(property);
         if (map == null) {
             map = new HashMap<Object, AggregationStrategy>();
+        } else {
+            // it is not safe to use the map directly as the exchange doesn't have the deep copy of it's properties
+            // we just create a new copy if we need to change the map
+            map = new HashMap<Object, AggregationStrategy>(map);
         }
         // store the strategy using this processor as the key
         // (so we can store multiple strategies on the same exchange)
