diff --git a/mock/mock.py b/mock/mock.py
index c776aff..c674a85 100644
--- a/mock/mock.py
+++ b/mock/mock.py
@@ -79,21 +79,6 @@
 except AttributeError:
     import funcsigs
     inspectsignature = funcsigs.signature
-    # Has funcsigs been fixed?
-    try:
-        class F:
-            def f(a, self):
-                pass
-        inspectsignature(partial(F.f, None)).bind(self=10)
-    except TypeError:
-        def fixedbind(*args, **kwargs):
-            self = args[0]
-            args = args[1:]
-            return self._bind(args, kwargs)
-        funcsigs.Signature.bind = fixedbind
-        del fixedbind
-    finally:
-        del F
 
 
 # TODO: use six.
diff --git a/requirements.txt b/requirements.txt
index 5e2d881..31bbe5d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,4 @@
-funcsigs;python_version<"3.3"
+funcsigs>=1;python_version<"3.3"
 # For runtime needs this is correct. For setup_requires needs, 1.2.0 is needed
 # but setuptools can't cope with conflicts in setup_requires, so thats
 # unversioned.