updated for version 7.0181
diff --git a/src/po/Makefile b/src/po/Makefile
index a064888..185bc2a 100644
--- a/src/po/Makefile
+++ b/src/po/Makefile
@@ -202,11 +202,14 @@
 	  exit 1; \
 	fi
 
-clean:
-	rm -f core core.* *.old.po *.mo *.ck *.pot sjiscorr
+clean: checkclean
+	rm -f core core.* *.old.po *.mo *.pot sjiscorr
 
 distclean: clean
 
+checkclean:
+	rm -f *.ck
+
 #
 # NOTE: If you get an error for gvimext.cpp not found, you need to unpack the
 # extra archive.