Index: Lib/os.py
===================================================================
--- Lib/os.py	(revision 74553)
+++ Lib/os.py	(working copy)
@@ -668,9 +668,11 @@
             msg = "os.popen2 is deprecated.  Use the subprocess module."
             warnings.warn(msg, DeprecationWarning, stacklevel=2)
 
+            use_shell = isinstance(cmd, basestring)
+
             import subprocess
             PIPE = subprocess.PIPE
-            p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
+            p = subprocess.Popen(cmd, shell=use_shell, bufsize=bufsize,
                                  stdin=PIPE, stdout=PIPE, close_fds=True)
             return p.stdin, p.stdout
         __all__.append("popen2")
@@ -687,9 +689,11 @@
             msg = "os.popen3 is deprecated.  Use the subprocess module."
             warnings.warn(msg, DeprecationWarning, stacklevel=2)
 
+            use_shell = isinstance(cmd, basestring)
+            
             import subprocess
             PIPE = subprocess.PIPE
-            p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
+            p = subprocess.Popen(cmd, shell=use_shell, bufsize=bufsize,
                                  stdin=PIPE, stdout=PIPE, stderr=PIPE,
                                  close_fds=True)
             return p.stdin, p.stdout, p.stderr
@@ -707,9 +711,11 @@
             msg = "os.popen4 is deprecated.  Use the subprocess module."
             warnings.warn(msg, DeprecationWarning, stacklevel=2)
 
+            use_shell = isinstance(cmd, basestring)
+
             import subprocess
             PIPE = subprocess.PIPE
-            p = subprocess.Popen(cmd, shell=True, bufsize=bufsize,
+            p = subprocess.Popen(cmd, shell=use_shell, bufsize=bufsize,
                                  stdin=PIPE, stdout=PIPE,
                                  stderr=subprocess.STDOUT, close_fds=True)
             return p.stdin, p.stdout
Index: Lib/test/test_popen2.py
===================================================================
--- Lib/test/test_popen2.py	(revision 74553)
+++ Lib/test/test_popen2.py	(working copy)
@@ -78,6 +78,16 @@
 
     def test_os_popen2(self):
         # same test as test_popen2(), but using the os.popen*() API
+        if os.name == 'posix':
+            w, r = os.popen2([self.cmd])
+            self.validate_output(self.teststr, self.expected, r, w)
+
+            # Make sure to test the list form of a command with an argument,
+            # too.
+            w, r = os.popen2(["echo", self.teststr])
+            got = r.read()
+            self.assertEquals(got, self.teststr + "\n")
+
         w, r = os.popen2(self.cmd)
         self.validate_output(self.teststr, self.expected, r, w)
 
@@ -87,10 +97,32 @@
             w, r, e = os.popen3([self.cmd])
             self.validate_output(self.teststr, self.expected, r, w, e)
 
+            # Make sure to test the list form of a command with an argument,
+            # too.
+            w, r, e = os.popen3(["echo", self.teststr])
+            got = r.read()
+            self.assertEquals(got, self.teststr + "\n")
+            got = e.read()
+            self.assertFalse(got, "unexpected %r on stderr" % got)
+
         w, r, e = os.popen3(self.cmd)
         self.validate_output(self.teststr, self.expected, r, w, e)
 
+    def test_os_popen4(self):
+        if os.name == 'posix':
+            w, r = os.popen4([self.cmd])
+            self.validate_output(self.teststr, self.expected, r, w)
 
+            # Make sure to test the list form of a command with an argument,
+            # too.
+            w, r = os.popen4(["echo", self.teststr])
+            got = r.read()
+            self.assertEquals(got, self.teststr + "\n")
+
+        w, r = os.popen4(self.cmd)
+        self.validate_output(self.teststr, self.expected, r, w)
+
+
 def test_main():
     run_unittest(Popen2Test)