fix bug

cat-core/src/main/java/com/dianping/cat/build/ComponentsConfigurator.java

@@ -49,7 +49,7 @@ public class ComponentsConfigurator extends AbstractResourceConfigurator {
 		all.add(C(MessageAnalyzerManager.class, DefaultMessageAnalyzerManager.class));
 
 		all.add(C(TcpSocketReceiver.class).req(ServerConfigManager.class).req(ServerStatisticManager.class)
-		      .req(MessageCodec.class, PlainTextMessageCodec.ID));
+		      .req(MessageCodec.class, PlainTextMessageCodec.ID).req(MessageHandler.class));
 
 		all.add(C(MessageHandler.class, DefaultMessageHandler.class));
 

cat-core/src/main/resources/META-INF/plexus/components.xml

@@ -59,6 +59,9 @@
 					<role>com.dianping.cat.message.spi.MessageCodec</role>
 					<role-hint>plain-text</role-hint>
 				</requirement>
+				<requirement>
+					<role>com.dianping.cat.message.spi.core.MessageHandler</role>
+				</requirement>
 			</requirements>
 		</component>
 		<component>