--- cpython-302424b84b07/Modules/signalmodule.c	2011-06-01 02:39:38.000000000 +0000
+++ cpython/Modules/signalmodule.c	2011-06-09 11:39:28.000000000 +0000
@@ -662,7 +662,9 @@
     if (iterable_to_sigset(signals, &set))
         return NULL;
 
+    Py_BEGIN_ALLOW_THREADS
     err = sigwait(&set, &signum);
+    Py_END_ALLOW_THREADS
     if (err) {
         errno = err;
         return PyErr_SetFromErrno(PyExc_OSError);