diff --git a/CHANGELOG b/CHANGELOG
index 09317c8f5..ddc3b0f18 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,7 @@
 Changes between 2.1.1 and [NEXT VERSION]
 ----------------------------------------
 
+- refine test discovery by package/module name (--pyargs), thanks Florian Mayer
 - fix issue69 / assertion rewriting fixed on some boolean operations
 - fix issue68 / packages now work with assertion rewriting
 - fix issue66: use different assertion rewriting caches when the -O option is passed
diff --git a/_pytest/__init__.py b/_pytest/__init__.py
index abc2fffe8..97d05f077 100644
--- a/_pytest/__init__.py
+++ b/_pytest/__init__.py
@@ -1,2 +1,2 @@
 #
-__version__ = '2.1.1'
+__version__ = '2.1.2.dev1'
diff --git a/_pytest/main.py b/_pytest/main.py
index ac306a867..d0d7c2dc3 100644
--- a/_pytest/main.py
+++ b/_pytest/main.py
@@ -2,7 +2,7 @@
 
 import py
 import pytest, _pytest
-import os, sys
+import os, sys, imp
 tracebackcutdir = py.path.local(_pytest.__file__).dirpath()
 
 # exitcodes for the command line
@@ -469,16 +469,22 @@ class Session(FSCollector):
         return True
 
     def _tryconvertpyarg(self, x):
-        try:
-            mod = __import__(x, None, None, ['__doc__'])
-        except (ValueError, ImportError):
-            return x
-        p = py.path.local(mod.__file__)
-        if p.purebasename == "__init__":
-            p = p.dirpath()
-        else:
-            p = p.new(basename=p.purebasename+".py")
-        return str(p)
+        mod = None
+        path = [os.path.abspath('.')] + sys.path
+        for name in x.split('.'):
+            try:
+                fd, mod, type_ = imp.find_module(name, path)
+            except ImportError:
+                return x
+            else:
+                if fd is not None:
+                    fd.close()
+            
+            if type_[2] != imp.PKG_DIRECTORY:
+                path = [os.path.dirname(mod)]
+            else:
+                path = [mod]
+        return mod
 
     def _parsearg(self, arg):
         """ return (fspath, names) tuple after checking the file exists. """
diff --git a/setup.py b/setup.py
index d6827bd0d..ce058de48 100644
--- a/setup.py
+++ b/setup.py
@@ -24,7 +24,7 @@ def main():
         name='pytest',
         description='py.test: simple powerful testing with Python',
         long_description = long_description,
-        version='2.1.1',
+        version='2.1.2.dev1',
         url='http://pytest.org',
         license='MIT license',
         platforms=['unix', 'linux', 'osx', 'cygwin', 'win32'],
diff --git a/testing/acceptance_test.py b/testing/acceptance_test.py
index 6b815e4d7..716d3c3ce 100644
--- a/testing/acceptance_test.py
+++ b/testing/acceptance_test.py
@@ -231,7 +231,7 @@ class TestGeneralUsage:
         res = testdir.runpytest(p)
         assert res.ret == 0
         res.stdout.fnmatch_lines(["*1 skipped*"])
-        
+
     def test_direct_addressing_selects(self, testdir):
         p = testdir.makepyfile("""
             def pytest_generate_tests(metafunc):
@@ -364,7 +364,7 @@ class TestInvocationVariants:
         retcode = testdir.pytestmain(testdir.tmpdir)
         assert not retcode
         out, err = capsys.readouterr()
-        
+
     def test_invoke_plugin_api(self, capsys):
         class MyPlugin:
             def pytest_addoption(self, parser):
@@ -374,6 +374,19 @@ class TestInvocationVariants:
         out, err = capsys.readouterr()
         assert "--myopt" in out
 
+    def test_pyargs_importerror(self, testdir, monkeypatch):
+        monkeypatch.delenv('PYTHONDONTWRITEBYTECODE', False)
+        path = testdir.mkpydir("tpkg")
+        path.join("test_hello.py").write('raise ImportError')
+
+        result = testdir.runpytest("--pyargs", "tpkg.test_hello")
+        assert result.ret != 0
+        # FIXME: It would be more natural to match NOT
+        # "ERROR*file*or*package*not*found*".
+        result.stdout.fnmatch_lines([
+            "*collected 0 items*"
+        ])
+
     def test_cmdline_python_package(self, testdir, monkeypatch):
         monkeypatch.delenv('PYTHONDONTWRITEBYTECODE', False)
         path = testdir.mkpydir("tpkg")