diff --git a/var/spack/repos/builtin/packages/tetgen/package.py b/var/spack/repos/builtin/packages/tetgen/package.py
index 7ac55a678575ffd12860b69d7e063ff25e4b2667..6e5ed79c36ad3a83040a0eca1fb8b88cf95cefb9 100644
--- a/var/spack/repos/builtin/packages/tetgen/package.py
+++ b/var/spack/repos/builtin/packages/tetgen/package.py
@@ -22,7 +22,9 @@
 # License along with this program; if not, write to the Free Software
 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ##############################################################################
+
 from spack import *
+import glob
 
 
 class Tetgen(Package):
@@ -33,13 +35,35 @@ class Tetgen(Package):
     """
 
     homepage = "http://www.tetgen.org"
-    url      = "http://www.tetgen.org/files/tetgen1.4.3.tar.gz"
 
-    version('1.4.3', 'd6a4bcdde2ac804f7ec66c29dcb63c18')
-    version('1.5.0', '3b9fd9cdec121e52527b0308f7aad5c1',
-            url='http://www.tetgen.org/1.5/src/tetgen1.5.0.tar.gz')
+    version('1.5.0', '3b9fd9cdec121e52527b0308f7aad5c1', url='http://www.tetgen.org/1.5/src/tetgen1.5.0.tar.gz')
+    version('1.4.3', 'd6a4bcdde2ac804f7ec66c29dcb63c18', url='http://www.tetgen.org/files/tetgen1.4.3.tar.gz')
+
+    variant('debug', default=False, description='Builds the library in debug mode.')
+    variant('except', default=False, description='Replaces asserts with exceptions for better C++ compatibility.')
+
+    patch('tetgen-1.5.0-free.patch', when='@1.5.0')
+
+    def patch(self):
+        cflags = '-g -O0' if '+debug' in self.spec else '-g0 -O3'
+
+        mff = FileFilter('makefile')
+        mff.filter(r'^(C(XX)?FLAGS\s*=)(.*)$', r'\1 {0}'.format(cflags))
+
+        if '+except' in self.spec:
+            hff = FileFilter('tetgen.h')
+            hff.filter(r'(\b)(throw)(\b)(.*);', r'\1assert_throw(false);')
+            hff.filter(r'^(#define\s*tetgenH\s*)$', r'\1{0}'.format("""\n
+#include <stdexcept>
+
+inline void assert_throw(bool assertion)
+{
+  if(!assertion)
+    throw std::runtime_error("Tetgen encountered a problem (assert failed)!");
+}\n"""))
 
-    depends_on('cmake@2.8.7:', when='@1.5.0:', type='build')
+            sff = FileFilter(*(glob.glob('*.cxx')))
+            sff.filter(r'(\b)(assert)(\b)', r'\1assert_throw\3')
 
     def install(self, spec, prefix):
         make('tetgen', 'tetlib')
diff --git a/var/spack/repos/builtin/packages/tetgen/tetgen-1.5.0-free.patch b/var/spack/repos/builtin/packages/tetgen/tetgen-1.5.0-free.patch
new file mode 100644
index 0000000000000000000000000000000000000000..009ccd834f589c1f36eb412dd91e91bd0bc636e7
--- /dev/null
+++ b/var/spack/repos/builtin/packages/tetgen/tetgen-1.5.0-free.patch
@@ -0,0 +1,49 @@
+diff --git a/tetgen.h b/tetgen.h
+index 3196e03..2ff3138 100644
+--- a/tetgen.h
++++ b/tetgen.h
+@@ -2206,6 +2206,44 @@ public:
+     if (highordertable != NULL) {
+       delete [] highordertable;
+     }
++
++    bgm = NULL;
++
++    points = NULL;
++    dummypoint = NULL;
++
++    tetrahedrons = NULL;
++
++    subfaces = NULL;
++    subsegs = NULL;
++
++    tet2segpool = NULL;
++    tet2subpool = NULL;
++
++    flippool = NULL;
++    unflipqueue = NULL;
++
++    cavetetlist = NULL;
++    cavebdrylist = NULL;
++    caveoldtetlist = NULL;
++    cavetetvertlist = NULL;
++
++    caveshlist = NULL;
++    caveshbdlist = NULL;
++    cavesegshlist = NULL;
++    cavetetshlist = NULL;
++    cavetetseglist = NULL;
++    caveencshlist = NULL;
++    caveencseglist = NULL;
++
++    subsegstack = NULL;
++    subfacstack = NULL;
++    subvertstack = NULL;
++
++    idx2facetlist = NULL;
++    facetverticeslist = NULL;
++    segmentendpointslist = NULL;
++    highordertable = NULL;
+   }
+ 
+   ~tetgenmesh()