diff --git a/src/Orchard.Tests/Events/EventTests.cs b/src/Orchard.Tests/Events/EventTests.cs
index 8aee2b481..94d9ec75d 100644
--- a/src/Orchard.Tests/Events/EventTests.cs
+++ b/src/Orchard.Tests/Events/EventTests.cs
@@ -22,13 +22,13 @@ namespace Orchard.Tests.Events {
             builder.RegisterType<StubExceptionPolicy>().As<IExceptionPolicy>();
 
             builder.RegisterType<StubEventHandler2>()
-                .Named(typeof(ITestEventHandler).Name.ToLowerInvariant(), typeof(IEventHandler))
-                .Named(typeof(IEventHandler).Name.ToLowerInvariant(), typeof(IEventHandler))
-                .WithMetadata("Interfaces", typeof(StubEventHandler2).GetInterfaces().ToLookup(i => i.Name, StringComparer.OrdinalIgnoreCase));
+                .Named(typeof(ITestEventHandler).Name, typeof(IEventHandler))
+                .Named(typeof(IEventHandler).Name, typeof(IEventHandler))
+                .WithMetadata("Interfaces", typeof(StubEventHandler2).GetInterfaces().ToLookup(i => i.Name));
             builder.RegisterInstance(_eventHandler)
-                .Named(typeof(ITestEventHandler).Name.ToLowerInvariant(), typeof(IEventHandler))
-                .Named(typeof(IEventHandler).Name.ToLowerInvariant(), typeof(IEventHandler))
-                .WithMetadata("Interfaces", typeof(StubEventHandler).GetInterfaces().ToLookup(i => i.Name, StringComparer.OrdinalIgnoreCase));
+                .Named(typeof(ITestEventHandler).Name, typeof(IEventHandler))
+                .Named(typeof(IEventHandler).Name, typeof(IEventHandler))
+                .WithMetadata("Interfaces", typeof(StubEventHandler).GetInterfaces().ToLookup(i => i.Name));
 
             _container = builder.Build();
             _eventBus = _container.Resolve<IEventBus>();
diff --git a/src/Orchard/Environment/ShellBuilders/ShellContainerFactory.cs b/src/Orchard/Environment/ShellBuilders/ShellContainerFactory.cs
index abae9e5dd..ff5dc4a28 100644
--- a/src/Orchard/Environment/ShellBuilders/ShellContainerFactory.cs
+++ b/src/Orchard/Environment/ShellBuilders/ShellContainerFactory.cs
@@ -83,11 +83,11 @@ namespace Orchard.Environment.ShellBuilders {
                         if (typeof(IEventHandler).IsAssignableFrom(item.Type)) {
                             var interfaces = item.Type.GetInterfaces();
                             foreach (var interfaceType in interfaces) {
-                                // Register named instance for each interface, for efficient filtering withing event bus
-                                registration = registration.Named(interfaceType.Name.ToLowerInvariant(), typeof (IEventHandler));
+                                // Register named instance for each interface, for efficient filtering inside event bus
+                                registration = registration.Named(interfaceType.Name, typeof (IEventHandler));
                             }
                             // Keep interfaces in metadata for performance
-                            registration = registration.WithMetadata("Interfaces", interfaces.ToLookup(i => i.Name, StringComparer.OrdinalIgnoreCase));
+                            registration = registration.WithMetadata("Interfaces", interfaces.ToLookup(i => i.Name));
                         }
 
                         foreach (var parameter in item.Parameters) {
diff --git a/src/Orchard/Events/DefaultOrchardEventBus.cs b/src/Orchard/Events/DefaultOrchardEventBus.cs
index 7e924f93e..3043a8d58 100644
--- a/src/Orchard/Events/DefaultOrchardEventBus.cs
+++ b/src/Orchard/Events/DefaultOrchardEventBus.cs
@@ -37,7 +37,7 @@ namespace Orchard.Events {
             string interfaceName = parameters[0];
             string methodName = parameters[1];
 
-            var eventHandlers = _eventHandlers[interfaceName.ToLowerInvariant()];
+            var eventHandlers = _eventHandlers[interfaceName];
             foreach (var eventHandler in eventHandlers) {
                 IEnumerable returnValue;
                 if (TryNotifyHandler(eventHandler, messageName, interfaceName, methodName, eventData, out returnValue)) {
@@ -74,7 +74,7 @@ namespace Orchard.Events {
         }
 
         private static bool TryInvokeMethod(IEventHandler eventHandler, Type interfaceType, string methodName, IDictionary<string, object> arguments, out IEnumerable returnValue) {
-            var key = String.Concat(eventHandler.GetType().FullName + "_" + interfaceType.Name, "_", methodName, "_", String.Join("_", arguments.Keys));
+            var key = eventHandler.GetType().FullName + "_" + interfaceType.Name + "_" + methodName + "_" + String.Join("_", arguments.Keys);
             var cachedDelegate = _delegateCache.GetOrAdd(key, k => {
                 var method = GetMatchingMethod(eventHandler, interfaceType, methodName, arguments);
                 return method != null