--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -585,6 +585,15 @@ def system(cmd, environ={}, cwd=None, on
         if cwd is not None and oldcwd != cwd:
             os.chdir(oldcwd)
 
+# os.path.lexists is not available on python2.3
+def lexists(filename):
+    "test whether a file with this name exists. does not follow symlinks"
+    try:
+        os.lstat(filename)
+    except:
+        return False
+    return True
+
 def rename(src, dst):
     """forcibly rename a file"""
     try: