Plugins can no longer register events while disabled

src/main/java/org/bukkit/plugin/IllegalPluginAccessException.java

@@ -0,0 +1,23 @@
+
+package org.bukkit.plugin;
+
+/**
+ * Thrown when a plugin attempts to interact with the server when it is not enabled
+ */
+public class IllegalPluginAccessException extends RuntimeException {
+
+    /**
+     * Creates a new instance of <code>IllegalPluginAccessException</code> without detail message.
+     */
+    public IllegalPluginAccessException() {
+    }
+
+
+    /**
+     * Constructs an instance of <code>IllegalPluginAccessException</code> with the specified detail message.
+     * @param msg the detail message.
+     */
+    public IllegalPluginAccessException(String msg) {
+        super(msg);
+    }
+}

src/main/java/org/bukkit/plugin/SimplePluginManager.java

@@ -270,8 +270,9 @@ public final class SimplePluginManager implements PluginManager {
      */
     public void registerEvent(Event.Type type, Listener listener, Priority priority, Plugin plugin) {
         if (!plugin.isEnabled()) {
-            server.getLogger().warning("Plugin '" + plugin.getDescription().getName() + "' (ver " + plugin.getDescription().getVersion() + ") is registering events before it is enabled. It may be misbehaving and the author needs to fix this.");
+            throw new IllegalPluginAccessException("Plugin attempted to register " + type + " while not enabled");
         }
+
         getEventListeners( type ).add(new RegisteredListener(listener, priority, plugin, type));
     }
 
@@ -285,6 +286,10 @@ public final class SimplePluginManager implements PluginManager {
      * @param plugin Plugin to register
      */
     public void registerEvent(Event.Type type, Listener listener, EventExecutor executor, Priority priority, Plugin plugin) {
+        if (!plugin.isEnabled()) {
+            throw new IllegalPluginAccessException("Plugin attempted to register " + type + " while not enabled");
+        }
+
         getEventListeners( type ).add(new RegisteredListener(listener, executor, priority, plugin));
     }