diff --git a/math/Makefile b/math/Makefile
index fa53f3fbd74..40fff581bcf 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.18 2001/01/23 15:55:02 kevlo Exp $
+# $OpenBSD: Makefile,v 1.19 2001/01/24 08:22:47 kevlo Exp $
 #
 
 #    SUBDIR += Scilab
@@ -36,6 +36,7 @@
      SUBDIR += p5-AI-NeuralNet-Mesh
      SUBDIR += p5-AI-Perceptron
 #    SUBDIR += p5-MatrixReal
+     SUBDIR += p5-Set-IntSpan
 #    SUBDIR += pari
 #    SUBDIR += plplot
 #    SUBDIR += r