diff --git a/pytools/mpi.py b/pytools/mpi.py
index 51ce7ff3c0bb203ae91e41745551a6c7db5cd07a..a575c0752d46d6322717be316bd5dbfc4e46b252 100644
--- a/pytools/mpi.py
+++ b/pytools/mpi.py
@@ -1,16 +1,28 @@
-def in_mpi_relaunch():
-    import os
-    return "PYTOOLS_RUN_WITHIN_MPI" in os.environ
+def check_for_mpi_relaunch(argv):
+    if argv[1] != "--mpi-relaunch":
+        return
+
+    from pickle import loads
+    f, args, kwargs = loads(argv[2])
+
+    f(*args, **kwargs)
+    import sys
+    sys.exit()
 
-def run_with_mpi_ranks(py_script, ranks, callable, *args, **kwargs):
-    if in_mpi_relaunch():
-        callable(*args, **kwargs)
-    else:
-        import sys, os
-        newenv = os.environ.copy()
-        newenv["PYTOOLS_RUN_WITHIN_MPI"] = "1"
 
-        from subprocess import check_call
-        check_call(["mpirun", "-np", str(ranks), 
-            sys.executable, py_script], env=newenv)
+def run_with_mpi_ranks(py_script, ranks, callable, args=(), kwargs=None):
+    if kwargs is None:
+        kwargs = {}
+
+    import sys
+    import os
+    newenv = os.environ.copy()
+    newenv["PYTOOLS_RUN_WITHIN_MPI"] = "1"
+
+    from pickle import dumps
+    callable_and_args = dumps((callable, args, kwargs))
 
+    from subprocess import check_call
+    check_call(["mpirun", "-np", str(ranks),
+        sys.executable, py_script, "--mpi-relaunch", callable_and_args],
+        env=newenv)