diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/TcpSocketServer.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/TcpSocketServer.java
index aacdfb8..befa47d 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/TcpSocketServer.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/TcpSocketServer.java
@@ -181,13 +181,13 @@
      */
     public static void main(final String[] args) throws Exception {
         if (args.length < 1 || args.length > 2) {
-            System.err.println("Incorrect number of arguments");
+            System.err.println("Incorrect number of arguments: " + args.length);
             printUsage();
             return;
         }
         final int port = Integer.parseInt(args[0]);
         if (port <= 0 || port >= MAX_PORT) {
-            System.err.println("Invalid port number");
+            System.err.println("Invalid port number: " + port);
             printUsage();
             return;
         }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/UdpSocketServer.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/UdpSocketServer.java
index 7cf386c..ce05b14 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/UdpSocketServer.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/net/server/UdpSocketServer.java
@@ -106,13 +106,13 @@
      */
     public static void main(final String[] args) throws Exception {
         if (args.length < 1 || args.length > 2) {
-            System.err.println("Incorrect number of arguments");
+            System.err.println("Incorrect number of arguments: " + args.length);
             printUsage();
             return;
         }
         final int port = Integer.parseInt(args[0]);
         if (port <= 0 || port >= MAX_PORT) {
-            System.err.println("Invalid port number");
+            System.err.println("Invalid port number:" + port);
             printUsage();
             return;
         }