mock<1.1.0 only for py2.6.
diff --git a/acme/setup.py b/acme/setup.py
index 6d820841490..5f1da239149 100644
--- a/acme/setup.py
+++ b/acme/setup.py
@@ -9,7 +9,6 @@
     # load_pem_private/public_key (>=0.6)
     # rsa_recover_prime_factors (>=0.8)
     'cryptography>=0.8',
-    'mock<1.1.0',  # py26
     'pyrfc3339',
     'ndg-httpsclient',  # urllib3 InsecurePlatformWarning (#304)
     'pyasn1',  # urllib3 InsecurePlatformWarning (#304)
@@ -23,8 +22,13 @@
 
 # env markers in extras_require cause problems with older pip: #517
 if sys.version_info < (2, 7):
-    # only some distros recognize stdlib argparse as already satisfying
-    install_requires.append('argparse')
+    install_requires.extend([
+        # only some distros recognize stdlib argparse as already satisfying
+        'argparse',
+        'mock<1.1.0',
+    ])
+else:
+    install_requires.append('mock')
 
 testing_extras = [
     'nose',
diff --git a/letsencrypt-apache/setup.py b/letsencrypt-apache/setup.py
index 39f4b68e1f9..5f1b0a95d21 100644
--- a/letsencrypt-apache/setup.py
+++ b/letsencrypt-apache/setup.py
@@ -1,3 +1,5 @@
+import sys
+
 from setuptools import setup
 from setuptools import find_packages
 
@@ -5,12 +7,16 @@
 install_requires = [
     'acme',
     'letsencrypt',
-    'mock<1.1.0',  # py26
     'python-augeas',
     'zope.component',
     'zope.interface',
 ]
 
+if sys.version_info < (2, 7):
+    install_requires.append('mock<1.1.0')
+else:
+    install_requires.append('mock')
+
 setup(
     name='letsencrypt-apache',
     packages=find_packages(),
diff --git a/letsencrypt-compatibility-test/setup.py b/letsencrypt-compatibility-test/setup.py
index f02041e55aa..99e66f54f0e 100644
--- a/letsencrypt-compatibility-test/setup.py
+++ b/letsencrypt-compatibility-test/setup.py
@@ -1,3 +1,5 @@
+import sys
+
 from setuptools import setup
 from setuptools import find_packages
 
@@ -7,10 +9,14 @@
     'letsencrypt-apache',
     'letsencrypt-nginx',
     'docker-py',
-    'mock<1.1.0',  # py26
     'zope.interface',
 ]
 
+if sys.version_info < (2, 7):
+    install_requires.append('mock<1.1.0')
+else:
+    install_requires.append('mock')
+
 setup(
     name='letsencrypt-compatibility-test',
     packages=find_packages(),
diff --git a/letsencrypt-nginx/setup.py b/letsencrypt-nginx/setup.py
index 92b974974b6..64742e7b6e2 100644
--- a/letsencrypt-nginx/setup.py
+++ b/letsencrypt-nginx/setup.py
@@ -1,3 +1,5 @@
+import sys
+
 from setuptools import setup
 from setuptools import find_packages
 
@@ -6,10 +8,14 @@
     'acme',
     'letsencrypt',
     'pyparsing>=1.5.5',  # Python3 support; perhaps unnecessary?
-    'mock<1.1.0',  # py26
     'zope.interface',
 ]
 
+if sys.version_info < (2, 7):
+    install_requires.append('mock<1.1.0')
+else:
+    install_requires.append('mock')
+
 setup(
     name='letsencrypt-nginx',
     packages=find_packages(),
diff --git a/letshelp-letsencrypt/setup.py b/letshelp-letsencrypt/setup.py
index 6b89a6d0920..7d42af88b8d 100644
--- a/letshelp-letsencrypt/setup.py
+++ b/letshelp-letsencrypt/setup.py
@@ -6,17 +6,17 @@
 
 install_requires = []
 if sys.version_info < (2, 7):
-    install_requires.append("mock<1.1.0")
+    install_requires.append('mock<1.1.0')
 else:
-    install_requires.append("mock")
+    install_requires.append('mock')
 
 setup(
-    name="letshelp-letsencrypt",
+    name='letshelp-letsencrypt',
     packages=find_packages(),
     install_requires=install_requires,
     entry_points={
         'console_scripts': [
-            "letshelp-letsencrypt-apache = letshelp_letsencrypt.apache:main",
+            'letshelp-letsencrypt-apache = letshelp_letsencrypt.apache:main',
         ],
     },
     include_package_data=True,
diff --git a/setup.py b/setup.py
index a40303e509f..5a7d75a5fe5 100644
--- a/setup.py
+++ b/setup.py
@@ -34,7 +34,6 @@ def read_file(filename, encoding='utf8'):
     'ConfigArgParse',
     'configobj',
     'cryptography>=0.7',  # load_pem_x509_certificate
-    'mock<1.1.0',  # py26
     'parsedatetime',
     'psutil>=2.1.0',  # net_connections introduced in 2.1.0
     'PyOpenSSL',
@@ -47,8 +46,13 @@ def read_file(filename, encoding='utf8'):
 
 # env markers in extras_require cause problems with older pip: #517
 if sys.version_info < (2, 7):
-    # only some distros recognize stdlib argparse as already satisfying
-    install_requires.append('argparse')
+    install_requires.extend([
+        # only some distros recognize stdlib argparse as already satisfying
+        'argparse',
+        'mock<1.1.0',
+    ])
+else:
+    install_requires.append('mock')
 
 dev_extras = [
     # Pin astroid==1.3.5, pylint==1.4.2 as a workaround for #289
