diff --git a/tests/run_tests.py b/tests/run_tests.py
index 4d2e0876b3..8d7c517d2a 100755
--- a/tests/run_tests.py
+++ b/tests/run_tests.py
@@ -40,26 +40,26 @@ parser.add_option("-s", "--script", action="store_true", dest="script",
                         and dashboard capability.")
 (options, args) = parser.parse_args()
 
-# Compiler paths
+# Default compiler paths
 FC='gfortran'
-MPI_DIR='/opt/mpich/3.0.4-gnu'
+MPI_DIR='/opt/mpich/3.1-gnu'
 HDF5_DIR='/opt/hdf5/1.8.12-gnu'
 PHDF5_DIR='/opt/phdf5/1.8.12-gnu'
-PETSC_DIR='/opt/petsc/3.4.3-gnu'
+PETSC_DIR='/opt/petsc/3.4.4-gnu'
 
 # Script mode for extra capability
 script_mode = False
 
 # Override default compiler paths if environmental vars are found
-if os.environ.has_key('FC'):
+if 'FC' in os.environ:
     FC = os.environ['FC']
-if os.environ.has_key('MPI_DIR'):
+if 'MPI_DIR' in os.environ:
     MPI_DIR = os.environ['MPI_DIR']
-if os.environ.has_key('HDF5_DIR'):
+if 'HDF5_DIR' in os.environ:
     HDF5_DIR = os.environ['HDF5_DIR']
-if os.environ.has_key('PHDF5_DIR'):
+if 'PHDF5_DIR' in os.environ:
     PHDF5_DIR = os.environ['PHDF5_DIR']
-if os.environ.has_key('PETSC_DIR'):
+if 'PETSC_DIR' in os.environ:
     PETSC_DIR = os.environ['PETSC_DIR']
 
 # CTest script template