Index: Lib/javaos.py
===================================================================
--- Lib/javaos.py	(revision 4218)
+++ Lib/javaos.py	(working copy)
@@ -100,6 +100,35 @@
 from os.path import curdir, pardir, sep, pathsep, defpath, extsep, altsep
 linesep = java.lang.System.getProperty('line.separator')
 
+from org.jruby.ext.posix import POSIXHandler, POSIXFactory
+from java.lang import System
+
+class PythonPOSIXHandler(POSIXHandler):
+    def error(self, errors, msg):
+        pass # implement
+    def unimplementedError(self, msg):
+        pass # implement
+    def warn(self, id, msg, rest):
+        pass # implement
+    def isVerbose(self):
+        return False
+    def getCurrentWorkingDirectory(self):
+        import os
+        return os.getcwd()
+    def getEnv(self):
+        import os
+        return os.environ
+    def getInputStream(self):
+        return System.in # handle resetting
+    def getOutputStream(self):
+        return System.out # handle resetting
+    def getPID(self):
+        return 0 # ???
+    def getErrorStream(self):
+        return System.err # handle resetting
+
+_posix = POSIXFactory.getPOSIX(PythonPosixHandler(), True)
+
 # open for reading only
 O_RDONLY = 0x0
 # open for writing only
@@ -221,6 +250,13 @@
         raise OSError(0, 'No such directory', path)
     return list(l)
 
+def chmod(path, mode):
+    """chmod(path, mode)
+
+    Change the access permissions of a file.
+    """
+    _posix.chmod(path, mode)
+
 def mkdir(path, mode='ignored'):
     """mkdir(path [, mode=0777])