diff --git a/Packages/Interval_arithmetic/version b/Packages/Interval_arithmetic/version
index cd103042a8e..bc874f7ab41 100644
--- a/Packages/Interval_arithmetic/version
+++ b/Packages/Interval_arithmetic/version
@@ -1 +1 @@
-4.166 (14 May 2003)
+4.167 (22 May 2003)