--- a/Lib/profile.py	Sat Nov 13 19:08:32 2010
+++ b/Lib/profile.py	Fri Mar 30 11:11:57 2012
@@ -509,12 +509,7 @@
         if self.__class__ is not Profile:
             raise TypeError("Subclasses must override .calibrate().")
 
-        saved_bias = self.bias
-        self.bias = 0
-        try:
-            return self._calibrate_inner(m, verbose)
-        finally:
-            self.bias = saved_bias
+        return self._calibrate_inner(m, verbose)
 
     def _calibrate_inner(self, m, verbose):
         get_time = self.get_time
@@ -546,7 +541,7 @@
         # elapsed_profile <- time f(m) takes with profiling.  The difference
         # is profiling overhead, only some of which the profiler subtracts
         # out on its own.
-        p = Profile()
+        p = Profile(timer=self.timer, bias=0)
         t0 = get_time()
         p.runctx('f(m)', globals(), locals())
         t1 = get_time()