diff --git a/CHANGELOG b/CHANGELOG
index 155f6fffa..a2a129fde 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,8 @@
 Changes between 2.3.5 and 2.4.DEV
 -----------------------------------
 
+- fix issue323 - sorting of many module-scoped arg parametrizations
+
 - add support for setUpModule/tearDownModule detection, thanks Brian Okken.
 
 - make sessionfinish hooks execute with the same cwd-context as at
diff --git a/_pytest/__init__.py b/_pytest/__init__.py
index 654c9a59a..0fcc78673 100644
--- a/_pytest/__init__.py
+++ b/_pytest/__init__.py
@@ -1,2 +1,2 @@
 #
-__version__ = '2.4.0.dev4'
+__version__ = '2.4.0.dev5'
diff --git a/_pytest/python.py b/_pytest/python.py
index 1c2b00bfa..db5d2cca2 100644
--- a/_pytest/python.py
+++ b/_pytest/python.py
@@ -1747,9 +1747,16 @@ def getfuncargnames(function, startindex=None):
 def parametrize_sorted(items, ignore, cache, scopenum):
     if scopenum >= 3:
         return items
+
+    # we pick the first item which has a arg/param combo in the
+    # requested scope and sort other items with the same combo
+    # into "newitems" which then is a list of all items using this
+    # arg/param.
+
     similar_items = []
     other_items = []
     slicing_argparam = None
+    slicing_index = 0
     for item in items:
         argparamlist = getfuncargparams(item, ignore, scopenum, cache)
         if slicing_argparam is None and argparamlist:
@@ -1759,7 +1766,8 @@ def parametrize_sorted(items, ignore, cache, scopenum):
             similar_items.append(item)
         else:
             other_items.append(item)
-    if similar_items:
+
+    if (len(similar_items) + slicing_index) > 1:
         newignore = ignore.copy()
         newignore.add(slicing_argparam)
         part2 = parametrize_sorted(
diff --git a/setup.py b/setup.py
index d8b32746b..c5e7890f7 100644
--- a/setup.py
+++ b/setup.py
@@ -12,7 +12,7 @@ def main():
         name='pytest',
         description='py.test: simple powerful testing with Python',
         long_description = long_description,
-        version='2.4.0.dev4',
+        version='2.4.0.dev5',
         url='http://pytest.org',
         license='MIT license',
         platforms=['unix', 'linux', 'osx', 'cygwin', 'win32'],
diff --git a/testing/python/metafunc.py b/testing/python/metafunc.py
index 71438870a..75e3aa461 100644
--- a/testing/python/metafunc.py
+++ b/testing/python/metafunc.py
@@ -555,6 +555,20 @@ class TestMetafuncFunctional:
         reprec = testdir.inline_run()
         reprec.assertoutcome(passed=5)
 
+    def test_parametrize_issue323(self, testdir):
+        testdir.makepyfile("""
+            import pytest
+
+            @pytest.fixture(scope='module', params=range(966))
+            def foo(request):
+                return request.param
+
+            def test_it(foo):
+                pass
+        """)
+        reprec = testdir.inline_run("--collectonly")
+        assert not reprec.getcalls("pytest_internalerror")
+
     def test_usefixtures_seen_in_generate_tests(self, testdir):
         testdir.makepyfile("""
             import pytest
diff --git a/tox.ini b/tox.ini
index 3af69e880..16e2c12d7 100644
--- a/tox.ini
+++ b/tox.ini
@@ -98,4 +98,4 @@ python_files=test_*.py *_test.py testing/*/*.py
 python_classes=Test Acceptance
 python_functions=test
 pep8ignore = E401 E225 E261 E128 E124 E302
-norecursedirs = .tox ja
+norecursedirs = .tox ja .hg