diff --git a/.travis.yml b/.travis.yml
index 958907e9..350b973b 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,7 +9,7 @@ language: python
 
 python:
 - 2.6
-- "2.7_with_system_site_packages"
+- 2.7
 - 3.2
 - 3.3
 - 3.4
@@ -18,6 +18,13 @@ before_install:
     - export DISPLAY=:99.0
     - export PYTHONWARNINGS="all"
     - export WHEELHOUSE="--no-index --find-links=http://travis-wheels.scikit-image.org/"
+    - sudo apt-get update
+
+    - virtualenv -p python ~/venv
+    - source ~/venv/bin/activate
+    - which python
+    - python --version
+
     - travis_retry tools/travis_setup.sh
 
     - python check_bento_build.py
diff --git a/requirements.txt b/requirements.txt
index 98f3b77f..9e5c9ba4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,7 +1,7 @@
 cython>=0.19.2
-matplotlib>=1.1.0
-numpy>=1.6.1
+matplotlib>=1.1.1
+numpy>=1.6.0
 scipy>=0.9
 six>=1.3
 networkx>=1.8
-pillow>=1.1.7
+pillow>=1.7.8
diff --git a/setup.py b/setup.py
index 1d7b3d1c..f9ec3a07 100755
--- a/setup.py
+++ b/setup.py
@@ -35,7 +35,7 @@ DEPENDENCIES = {}
 with open('requirements.txt', 'rb') as fid:
     data = fid.read().decode('utf-8', 'replace')
 for line in data.splitlines():
-    pkg, _, version_info = line.partition('>=')
+    pkg, _, version_info = line.replace('==', '>=').partition('>=')
     # Only require Cython if we have a developer checkout
     if pkg.lower() == 'cython' and not VERSION.endswith('dev'):
         continue
@@ -88,22 +88,29 @@ def check_requirements():
     for (package_name, min_version) in DEPENDENCIES.items():
         if package_name == 'cython':
             package_name = 'Cython'
-        dep_error = False
+        dep_error = ''
         if package_name.lower() == 'pillow':
             package_name = 'PIL.Image'
+            min_version = '1.1.7'
         try:
             package = __import__(package_name,
                 fromlist=[package_name.rpartition('.')[0]])
         except ImportError:
-            dep_error = True
+            dep_error = ('You need `%s` version %s or later.'
+                         % (package_name, min_version))
         else:
-            package_version = get_package_version(package)
+            if package_name == 'PIL':
+                package_version = package.PILLOW_VERSION
+            else:
+                package_version = get_package_version(package)
 
             if LooseVersion(min_version) > LooseVersion(package_version):
-                dep_error = True
+                dep_error = ('You need `%s` version %s or later,'
+                             'found version %s.'
+                             % (package_name, min_version,
+                                package_version))
         if dep_error:
-            raise ImportError('You need `%s` version %s or later.' \
-                              % (package_name, min_version))
+            raise ImportError(dep_error)
 
 
 if __name__ == "__main__":
diff --git a/tools/travis_install_optional.sh b/tools/travis_install_optional.sh
index ec01d899..b1de66de 100755
--- a/tools/travis_install_optional.sh
+++ b/tools/travis_install_optional.sh
@@ -10,7 +10,7 @@ if [[ $TRAVIS_PYTHON_VERSION == 2.7* ]]; then
 else
     sudo apt-get install -q libqt4-dev
     pip install -q PySide $WHEELHOUSE
-    python ~/virtualenv/python${TRAVIS_PYTHON_VERSION}/bin/pyside_postinstall.py -install
+    python ~/venv/bin/pyside_postinstall.py -install
 fi
 
 # imread does NOT support py3.2
diff --git a/tools/travis_setup.sh b/tools/travis_setup.sh
index e8227642..d9f46cd9 100755
--- a/tools/travis_setup.sh
+++ b/tools/travis_setup.sh
@@ -2,20 +2,26 @@
 set -ex
 
 sh -e /etc/init.d/xvfb start
-sudo apt-get update
 
 pip install wheel flake8 coveralls nose
-pip uninstall -y numpy
+
+# install system tk
+sudo apt-get install python-tk
 
 # on Python 2.7, use the system versions of numpy, scipy, and matplotlib
 # and the minimum version of cython and networkx
 if [[ $TRAVIS_PYTHON_VERSION == 2.7* ]]; then
     sudo apt-get install python-scipy python-matplotlib
-    pip install https://github.com/cython/cython/archive/0.19.2.tar.gz
-    pip install https://github.com/networkx/networkx/archive/networkx-1.8.tar.gz
+    sed -i 's/cython>=/cython==/g' requirements.txt
+    sed -i 's/networkx>=/networkx==/g' requirements.txt
 fi
 
-pip install -r requirements.txt $WHEELHOUSE
+# on Python 3.2, use matplotlib 1.3.1
+if [[ $TRAVIS_PYTHON_VERSION == 2.7* ]]; then
+    sed -i 's/matplotlib>=*.*.*/matplotlib==1.3.1/g' requirements.txt
+fi
+
+pip install $WHEELHOUSE -r requirements.txt
 
 # clean up disk space
 sudo apt-get clean