diff -Nru apache-tomcat-6.0.14-src.orig/java/org/apache/catalina/tribes/membership/McastServiceImpl.java apache-tomcat-6.0.14-src/java/org/apache/catalina/tribes/membership/McastServiceImpl.java
--- apache-tomcat-6.0.14-src.orig/java/org/apache/catalina/tribes/membership/McastServiceImpl.java	2007-07-20 04:21:20.000000000 +0200
+++ apache-tomcat-6.0.14-src/java/org/apache/catalina/tribes/membership/McastServiceImpl.java	2007-08-21 15:53:56.000000000 +0200
@@ -22,6 +22,7 @@
 import java.net.DatagramPacket;
 import java.net.InetAddress;
 import java.net.MulticastSocket;
+import java.net.BindException;
 
 import org.apache.catalina.tribes.MembershipListener;
 import java.util.Arrays;
@@ -162,8 +163,23 @@
     }
     
     protected void setupSocket() throws IOException {
-        if (mcastBindAddress != null) socket = new MulticastSocket(new InetSocketAddress(mcastBindAddress, port));
-        else socket = new MulticastSocket(port);
+        if (mcastBindAddress != null) {
+            try {
+                socket = new MulticastSocket(new InetSocketAddress(address,
+                                                                   port));
+            }
+            catch (BindException e) {
+                /*
+                 * On some plattforms (e.g. Linux) it is not possible to bind
+                 * to the multicast address. In this case only bind to the
+                 * port.
+                 */
+                socket = new MulticastSocket(port);
+            }
+        }
+        else {
+            socket = new MulticastSocket(port);
+        }
         socket.setLoopbackMode(false); //hint that we don't need loop back messages
         if (mcastBindAddress != null) {
 			if(log.isInfoEnabled())