diff --git a/.travis.yml b/.travis.yml
index 350b973b..e3766925 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,13 +20,11 @@ before_install:
     - export WHEELHOUSE="--no-index --find-links=http://travis-wheels.scikit-image.org/"
     - sudo apt-get update
 
-    - virtualenv -p python ~/venv
+    - travis_retry tools/travis_setup.sh
+
     - source ~/venv/bin/activate
     - which python
     - python --version
-
-    - travis_retry tools/travis_setup.sh
-
     - python check_bento_build.py
 
     - tools/header.py "Dependency versions"
diff --git a/requirements.txt b/requirements.txt
index 9e5c9ba4..189b627b 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,6 +1,6 @@
 cython>=0.19.2
-matplotlib>=1.1.1
-numpy>=1.6.0
+matplotlib>=1.1.0
+numpy>=1.6.1
 scipy>=0.9
 six>=1.3
 networkx>=1.8
diff --git a/tools/travis_install_optional.sh b/tools/travis_install_optional.sh
index b1de66de..582503bd 100755
--- a/tools/travis_install_optional.sh
+++ b/tools/travis_install_optional.sh
@@ -7,6 +7,21 @@ tools/header.py "Install optional dependencies"
 if [[ $TRAVIS_PYTHON_VERSION == 2.7* ]]; then
     sudo apt-get install -q python-qt4
 
+    # http://stackoverflow.com/a/9716100
+    LIBS=( PyQt4 sip.so )
+
+    PYTHON_VERSION=python$(python -c "import sys; print (str(sys.version_info[0])+'.'+str(sys.version_info[1]))")
+    VAR=( $(which -a $PYTHON_VERSION) )
+
+    GET_PYTHON_LIB_CMD="from distutils.sysconfig import get_python_lib; print (get_python_lib())"
+    LIB_VIRTUALENV_PATH=$(python -c "$GET_PYTHON_LIB_CMD")
+    LIB_SYSTEM_PATH=$(${VAR[-1]} -c "$GET_PYTHON_LIB_CMD")
+
+    for LIB in ${LIBS[@]}
+    do
+        ln -s $LIB_SYSTEM_PATH/$LIB $LIB_VIRTUALENV_PATH/$LIB
+    done
+
 else
     sudo apt-get install -q libqt4-dev
     pip install -q PySide $WHEELHOUSE
@@ -25,7 +40,7 @@ if [[ $TRAVIS_PYTHON_VERSION != 3.4 ]]; then
 fi
 
 sudo apt-get install -q libfreeimage3
-pip install -q astropy
+pip install -q astropy $WHEELHOUSE
 
 if [[ $TRAVIS_PYTHON_VERSION == 2.* ]]; then
     pip install -q pyamg
diff --git a/tools/travis_setup.sh b/tools/travis_setup.sh
index d9f46cd9..5b91a976 100755
--- a/tools/travis_setup.sh
+++ b/tools/travis_setup.sh
@@ -3,19 +3,24 @@ set -ex
 
 sh -e /etc/init.d/xvfb start
 
-pip install wheel flake8 coveralls nose
-
-# 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
+    virtualenv -p python --system-site-packages ~/venv
     sudo apt-get install python-scipy python-matplotlib
     sed -i 's/cython>=/cython==/g' requirements.txt
     sed -i 's/networkx>=/networkx==/g' requirements.txt
+else
+    virtualenv -p python --system-site-packages ~/venv
 fi
 
+source ~/venv/bin/activate
+pip install wheel flake8 coveralls nose
+
+# install system tk for matplotlib
+sudo apt-get install python-tk
+
+
 # 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