diff --git a/Makefile b/Makefile
index 17771ab..d295e0e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-KFVER=121
+KFVER=1_2_1
 
 DISTDIR=kiss_fft_v$(KFVER)
 TARBALL=kiss_fft_v$(KFVER).tar.gz