diff --git a/Lib/test/test_mmap.py b/Lib/test/test_mmap.py
index 417080f..69d3cd5 100644
--- a/Lib/test/test_mmap.py
+++ b/Lib/test/test_mmap.py
@@ -297,6 +297,24 @@
         except OSError:
             pass
 
+    # make sure a double close doesn't crash on Solaris (Bug# 665913)
+    f = open(TESTFN, 'w+')
+
+    try:    # unlink TESTFN no matter what
+        f.write(2**24 * 'a') # Arbitrary character
+        f.close()
+
+        f = open(TESTFN)
+        mf = mmap.mmap(f.fileno(), 2**24, access=mmap.ACCESS_READ)
+        mf.close()
+        mf.close()
+        f.close()
+
+    finally:
+        try:
+            os.unlink(TESTFN)
+        except OSError:
+            pass
 
 
     print ' Test passed'
diff --git a/Modules/mmapmodule.c b/Modules/mmapmodule.c
index cff3c14..f1df4dc 100644
--- a/Modules/mmapmodule.c
+++ b/Modules/mmapmodule.c
@@ -141,8 +141,10 @@
 #endif /* MS_WINDOWS */
 
 #ifdef UNIX
-	munmap(self->data, self->size);
-	self->data = NULL;
+	if (self->data != NULL) {
+		munmap(self->data, self->size);
+		self->data = NULL;
+	}
 #endif
 
 	Py_INCREF (Py_None);