diff --git a/src/Orchard/Events/DefaultOrchardEventBus.cs b/src/Orchard/Events/DefaultOrchardEventBus.cs
index d02c02195..6e1d4de4d 100644
--- a/src/Orchard/Events/DefaultOrchardEventBus.cs
+++ b/src/Orchard/Events/DefaultOrchardEventBus.cs
@@ -73,7 +73,7 @@ namespace Orchard.Events {
         }
 
         private static bool TryInvokeMethod(IEventHandler eventHandler, Type interfaceType, string methodName, IDictionary<string, object> arguments, out IEnumerable returnValue) {
-            MethodInfo method = _interfaceMethodsCache.GetOrAdd(String.Concat(interfaceType.Name, "_", methodName, "_", String.Join("_", arguments.Keys)), GetMatchingMethod(eventHandler, interfaceType, methodName, arguments));
+            MethodInfo method = _interfaceMethodsCache.GetOrAdd(String.Concat(eventHandler.GetType().Name + "_" + interfaceType.Name, "_", methodName, "_", String.Join("_", arguments.Keys)), GetMatchingMethod(eventHandler, interfaceType, methodName, arguments));
 
             if (method != null) {
                 var parameters = new List<object>();