diff -urN buildbot-slave-0.8.5.orig/buildslave/runprocess.py buildbot-slave-0.8.5/buildslave/runprocess.py
--- buildbot-slave-0.8.5.orig/buildslave/runprocess.py	2011-09-03 23:59:10 +0400
+++ buildbot-slave-0.8.5/buildslave/runprocess.py	2012-11-02 03:08:05 +0400
@@ -24,6 +24,7 @@
 import re
 import subprocess
 import traceback
+import tempfile
 import stat
 from collections import deque
 
@@ -36,6 +37,54 @@
 if runtime.platformType == 'posix':
     from twisted.internet.process import Process
 
+if os.name == 'nt':
+  import win32api
+  import win32process
+
+def safe_terminate_process (proc, code):
+  if os.name == 'nt':
+    cp = win32api.GetCurrentProcess ()
+    result = False
+    dupproc = win32api.DuplicateHandle (cp, proc._handle, cp, 2 | 1024 | 8 | 32 | 16, 0, 0)
+    try:
+      exitcode = win32process.GetExitCodeProcess (dupproc)
+      if exitcode == 0x103:
+        kernel32 = win32api.GetModuleHandle ("kernel32")
+        exitprocess = win32api.GetProcAddress (kernel32, "ExitProcess")
+        try:
+          th, tid = win32process.CreateRemoteThread (dupproc, None, 0, exitprocess, code, 0)
+          win32api.CloseHandle (th)
+        except:
+          pass
+        result = True
+      else:
+        result = True
+    # except failed to get exit code? failed to get module handle?
+    finally:
+      win32api.CloseHandle (dupproc)
+    return result
+  else:
+    return proc.kill ()
+
+class Dummy(object):
+  def SetHandle (self, h):
+    self._handle = h
+
+def safe_terminate_process_by_pid (proc, code):
+  if os.name == 'nt':
+    try:
+      openproc = win32api.OpenProcess (2 | 1024 | 8 | 32 | 16, 0, proc)
+      try:
+        d = Dummy ()
+        d.SetHandle (openproc)
+        safe_terminate_process (d, code)
+      finally:
+        win32api.CloseHandle (openproc)
+    except:
+      pass
+  else:
+    return os.kill (proc, code)
+
 def shell_quote(cmd_list):
     # attempt to quote cmd_list such that a shell will properly re-interpret
     # it.  The pipes module is only available on UNIX, and Windows "shell"
@@ -148,6 +197,7 @@
         self.pending_stdin = ""
         self.stdin_finished = False
         self.killed = False
+        self.scriptfile = ""
 
     def setStdin(self, data):
         assert not self.connected
@@ -198,6 +248,11 @@
                 rc = 1
             else:
                 rc = -1
+	if self.scriptfile:
+            try:
+                os.remove (self.scriptfile)
+            except:
+                pass
         self.command.finished(sig, rc)
 
 
@@ -400,30 +455,52 @@
 
         self.pp = RunProcessPP(self)
 
-        if type(self.command) in types.StringTypes:
-            if runtime.platformType  == 'win32':
-                argv = os.environ['COMSPEC'].split() # allow %COMSPEC% to have args
-                if '/c' not in argv: argv += ['/c']
-                argv += [self.command]
-            else:
-                # for posix, use /bin/sh. for other non-posix, well, doesn't
-                # hurt to try
-                argv = ['/bin/sh', '-c', self.command]
-            display = self.fake_command
-        else:
-            # On windows, CreateProcess requires an absolute path to the executable.
-            # When we call spawnProcess below, we pass argv[0] as the executable.
-            # So, for .exe's that we have absolute paths to, we can call directly
-            # Otherwise, we should run under COMSPEC (usually cmd.exe) to
-            # handle path searching, etc.
-            if runtime.platformType == 'win32' and not \
-                    (self.command[0].lower().endswith(".exe") and os.path.isabs(self.command[0])):
-                argv = os.environ['COMSPEC'].split() # allow %COMSPEC% to have args
-                if '/c' not in argv: argv += ['/c']
-                argv += list(self.command)
-            else:
-                argv = self.command
-            # Attempt to format this for use by a shell, although the process isn't perfect
+        if type(self.command) in types.StringTypes:
+            if runtime.platformType  == 'win32':
+                if os.environ['BUILDSLAVE_SHELL']:
+                    argv = os.environ['BUILDSLAVE_SHELL'].split() # allow %COMSPEC% to have args
+                    argv += [self.command]
+                else:
+                    argv = os.environ['COMSPEC'].split() # allow %COMSPEC% to have args
+                    if '/c' not in argv:
+                        argv += ['/c']
+                    argv += [self.command]
+            else:
+                # for posix, use /bin/sh. for other non-posix, well, doesn't
+                # hurt to try
+                argv = ['/bin/sh', '-c', self.command]
+            display = self.fake_command
+        else:
+            # On windows, CreateProcess requires an absolute path to the executable.
+            # When we call spawnProcess below, we pass argv[0] as the executable.
+            # So, for .exe's that we have absolute paths to, we can call directly
+            # Otherwise, we should run under COMSPEC (usually cmd.exe) to
+            # handle path searching, etc.
+            if runtime.platformType == 'win32' and not \
+                    (self.command[0].lower().endswith(".exe") and os.path.isabs(self.command[0])):
+                if os.environ['BUILDSLAVE_SHELL']:
+                    argv = os.environ['BUILDSLAVE_SHELL'].split()
+                    # Create a temporary script file that changes current directory
+                    # and runs the command we want
+                    # It will be deleted after command is finished running (see RunProcessPP)
+                    tf, tf_name = tempfile.mkstemp ()
+                    f = os.fdopen (tf, 'wb')
+                    fcontents = '#!/bin/sh\ncd {}\n{}'.format (
+                        re.sub(r'(?<!\\) ','\\ ', self.workdir.replace('\\','/')),
+                        ' '.join (self.command))
+                    f.write (fcontents)
+                    log.msg("Script: {}".format (fcontents))
+                    f.close ()
+                    self.pp.scriptfile = tf_name
+                    argv += [tf_name.replace('\\','/')]
+                else:
+                    argv = os.environ['COMSPEC'].split() # allow %COMSPEC% to have args
+                    if '/c' not in argv:
+                      argv += ['/c']
+                    argv += list(self.command)
+            else:
+                argv = self.command
+            # Attempt to format this for use by a shell, although the process isn't perfect
             display = shell_quote(self.fake_command)
 
         # $PWD usually indicates the current directory; spawnProcess may not
@@ -433,7 +510,7 @@
             self.environ['PWD'] = os.path.abspath(self.workdir)
 
         # self.stdin is handled in RunProcessPP.connectionMade
-
+	log.msg("Running {}".format (argv))
         log.msg(" " + display)
         self._addToBuffers('header', display+"\n")
 
@@ -764,9 +841,7 @@
             if self.KILL == None:
                 log.msg("self.KILL==None, only pretending to kill child")
             else:
-                log.msg("using TASKKILL /F PID /T to kill pid %s" % self.process.pid)
-                subprocess.check_call("TASKKILL /F /PID %s /T" % self.process.pid)
-                log.msg("taskkill'd pid %s" % self.process.pid)
+                safe_terminate_process_by_pid (self.process.pid, 1)
                 hit = 1
 
         # try signalling the process itself (works on Windows too, sorta)