diff --git a/source/de/anomic/server/serverBusyThread.java b/source/de/anomic/server/serverBusyThread.java
index e11cef462..907708c82 100644
--- a/source/de/anomic/server/serverBusyThread.java
+++ b/source/de/anomic/server/serverBusyThread.java
@@ -26,46 +26,77 @@ package de.anomic.server;
 
 public interface serverBusyThread extends serverThread {
 
+    /**
+     * sets a sleep time before execution of the job-loop
+     * @param milliseconds
+     */
     public void setStartupSleep(long milliseconds);
-    // sets a sleep time before execution of the job-loop
 
+    /**
+     * sets a sleep time for pauses between two jobs if the job returns false (idle)
+     * @param milliseconds
+     * @return
+     */
     public long setIdleSleep(long milliseconds);
-    // sets a sleep time for pauses between two jobs if the job returns false (idle)
 
+    /**
+     * sets a sleep time for pauses between two jobs if the job returns true (busy)
+     * @param milliseconds
+     * @return
+     */
     public long setBusySleep(long milliseconds);
-    // sets a sleep time for pauses between two jobs if the job returns true (busy)
  
+    /**
+     * sets minimum required amount of memory for the job execution
+     * @param freeBytes
+     */
     public void setMemPreReqisite(long freeBytes);
-    // sets minimum required amount of memory for the job execution
  
+    /**
+     * defines if the thread should obey the intermission command
+     * @param obey
+     */
     public void setObeyIntermission(boolean obey);
-    // defines if the thread should obey the intermission command
  
+    /**
+     * @return the total number of cycles of job execution with idle-result
+     */
     public long getIdleCycles();
-    // returns the total number of cycles of job execution with idle-result
  
+    /**
+     * @return the total number of cycles of job execution with busy-result
+     */
     public long getBusyCycles();
-    // returns the total number of cycles of job execution with busy-result
  
+    /**
+     * @return the total number of cycles where a job execution was omitted
+     *         because of memory shortage
+     */
     public long getOutOfMemoryCycles();
-    // returns the total number of cycles where
-    // a job execution was omitted because of memory shortage
  
+    /**
+     * @return the total time that this thread has slept so far
+     */
     public long getSleepTime();
-    // returns the total time that this thread has slept so far
  
+    /**
+     * the thread is forced to pause for a specific time
+     * if the thread is busy meanwhile, the pause is ommitted
+     * @param pause
+     */
     public void intermission(long pause);
-    // the thread is forced to pause for a specific time
-    // if the thread is busy meanwhile, the pause is ommitted
  
+    /**
+     * performes one job procedure; this loopes until terminate() is called
+     * @return true if it has done something, false if it is idle and does not expect to work on more for a longer time
+     */
     public boolean job() throws Exception;
-    // performes one job procedure; this loopes until terminate() is called
-    // job returns true if it has done something
-    // it returns false if it is idle and does not expect to work on more for a longer time
 
+    /**
+     * is called when an outOfMemoryCycle is performed
+     * this method should try to free some memory, so that the job can be executed
+     */
     public void freemem();
-    // is called when an outOfMemoryCycle is performed
-    // this method should try to free some memory, so that the job can be executed
 
     public void notifyThread();
 }
diff --git a/source/de/anomic/server/serverCore.java b/source/de/anomic/server/serverCore.java
index ef2c74d54..e900eaede 100644
--- a/source/de/anomic/server/serverCore.java
+++ b/source/de/anomic/server/serverCore.java
@@ -207,7 +207,7 @@ public final class serverCore extends serverAbstractBusyThread implements server
         this.sslSocketFactory = initSSLFactory();
 
         // init session parameter
-        maxBusySessions = Integer.valueOf(switchboard.getConfig("httpdMaxBusySessions","100")).intValue();
+        maxBusySessions = Math.max(1, Integer.valueOf(switchboard.getConfig("httpdMaxBusySessions","100")).intValue());
         busySessions = new ConcurrentHashMap<Session, Object>();
         
         // init servercore
@@ -323,7 +323,7 @@ public final class serverCore extends serverAbstractBusyThread implements server
             // idleThreadCheck();
             this.switchboard.handleBusyState(this.busySessions.size());
             if (log.isFinest()) this.log.logFinest("* waiting for connections, " + this.busySessions.size() + " sessions running");
-                        
+            
             announceThreadBlockApply();
             
             // wait for new connection
@@ -331,6 +331,14 @@ public final class serverCore extends serverAbstractBusyThread implements server
             
             announceThreadBlockRelease();
             
+            if(this.busySessions.size() >= this.maxBusySessions)
+            {
+                // immediatly close connection if too much sessions are still running
+                if (log.isFinest()) this.log.logFinest("* connections exceeding limit, closing new incoming connection from "+ controlSocket.getRemoteSocketAddress());
+                controlSocket.close();
+                return false;
+            }
+            
             final String cIP = clientAddress(controlSocket);
             //System.out.println("server bfHosts=" + bfHost.toString());
             if (bfHost.get(cIP) != null) {
@@ -645,11 +653,28 @@ public final class serverCore extends serverAbstractBusyThread implements server
                 } catch (final IOException e) {
                     e.printStackTrace();
                 }
-                if (busySessions != null) busySessions.remove(this);
+                if (busySessions != null)
+                {
+                    busySessions.remove(this);
+                    if(log.isFinest()) log.logFinest("* removed session "+ this.controlSocket.getRemoteSocketAddress() + this.request);
+                }
             }
             
         }
         
+        /*
+         * (non-Javadoc)
+         * 
+         * @see java.lang.Object#finalize()
+         */
+        protected void finalize() {
+            if (busySessions != null && busySessions.contains(this))
+            {
+                busySessions.remove(this);
+                if(log.isFinest()) log.logFinest("* removed session "+ this.controlSocket.getRemoteSocketAddress() + this.request);
+            }
+        }
+        
         private void listen() {
             try {
                 
diff --git a/source/de/anomic/tools/diskUsage.java b/source/de/anomic/tools/diskUsage.java
index 646cf7a3a..7d9473fa3 100644
--- a/source/de/anomic/tools/diskUsage.java
+++ b/source/de/anomic/tools/diskUsage.java
@@ -260,7 +260,7 @@ public class diskUsage {
                 } else if (dir != null) {
                     checkVolumesInUseUnix (dir);
                 } else {
-                	log.logSevere("directory is null: " + dir);
+                	log.logSevere("directory is null: " + element);
                 }
             } else {
                 try {