Index: /org/python/core/IOShutdownHook.java
===================================================================
--- /org/python/core/IOShutdownHook.java	(revision 0)
+++ /org/python/core/IOShutdownHook.java	(revision 0)
@@ -0,0 +1,13 @@
+package org.python.core;
+
+import java.util.Observable;
+
+
+public class IOShutdownHook extends Observable implements Runnable {
+
+	public void run() {
+		setChanged();
+		notifyObservers(this);
+	}
+
+}
Index: /org/python/core/Py.java
===================================================================
--- /org/python/core/Py.java	(revision 3122)
+++ /org/python/core/Py.java	(working copy)
@@ -13,7 +13,15 @@
     static java.util.Hashtable frozenModules;
 
     static boolean initialized;
-
+    public final static IOShutdownHook IO_SHUTDOWN_HOOK = new IOShutdownHook();
+    static {
+    	try {
+    		Runtime.getRuntime().addShutdownHook(new Thread(IO_SHUTDOWN_HOOK));
+    	} catch (SecurityException ex) {
+    		Py.writeError("file", "Can't register IO Shutdown Hook!");
+    	}
+    }
+    
     static class SingletonResolver implements Serializable {
         private String which;
         
Index: /org/python/core/PyFile.java
===================================================================
--- /org/python/core/PyFile.java	(revision 3122)
+++ /org/python/core/PyFile.java	(working copy)
@@ -2,6 +2,7 @@
 package org.python.core;
 
 import java.io.*;
+import java.util.*;
 
 // To do:
 // - readinto(array)
@@ -17,11 +18,17 @@
 public class PyFile extends PyObject
 {
 
-    private static class FileWrapper {
+    private static class FileWrapper implements Observer {
         protected boolean reading;
         protected boolean writing;
         protected boolean binary;
-
+        private Observable obs;
+        
+        public FileWrapper(){
+        	Py.IO_SHUTDOWN_HOOK.addObserver(this);
+        	this.obs = Py.IO_SHUTDOWN_HOOK;
+        }
+        
         void setMode(String mode) {
             reading = mode.indexOf('r') >= 0;
             writing = mode.indexOf('w') >= 0 || mode.indexOf("+") >= 0 ||
@@ -28,6 +35,20 @@
                       mode.indexOf('a') >= 0;
             binary  = mode.indexOf('b') >= 0;
         }
+        
+		public void update(Observable o, Object arg) {
+			try {
+				this.flush();
+			} catch (IOException ioex) {
+				ioex.printStackTrace();
+			}
+		}
+		
+		protected void unsubscribe() {
+			obs.deleteObserver(this);
+			obs = null;
+		}
+
         public String read(int n) throws java.io.IOException {
             throw new java.io.IOException("file not open for reading");
         }
@@ -126,8 +147,9 @@
 
         public void close() throws java.io.IOException {
             istream.close();
+        	unsubscribe();
         }
-
+        
         public Object __tojava__(Class cls) throws IOException {
             if (InputStream.class.isAssignableFrom(cls))
                 return istream;
@@ -136,6 +158,7 @@
     }
 
     private static class OutputStreamWrapper extends FileWrapper {
+    	
         private java.io.OutputStream ostream;
 
         public OutputStreamWrapper(java.io.OutputStream s) {
@@ -162,6 +185,7 @@
 
         public void close() throws java.io.IOException {
             ostream.close();
+        	super.unsubscribe();
         }
 
         public Object __tojava__(Class cls) throws IOException {
@@ -191,6 +215,7 @@
         public void close() throws java.io.IOException {
             ostream.close();
             istream.close();
+            unsubscribe();
         }
 
         public Object __tojava__(Class cls) throws IOException {
@@ -219,6 +244,7 @@
 
         public void close() throws java.io.IOException {
             writer.close();
+            unsubscribe();
         }
     }
 
@@ -472,6 +498,7 @@
             }
 
             file.close();
+            unsubscribe();
         }
 
         public void truncate(long position) throws java.io.IOException {
@@ -585,6 +612,7 @@
 
         public void close() throws java.io.IOException {
             file.close();
+            unsubscribe();
         }
 
         public void truncate(long position) throws java.io.IOException {