diff --git a/meta/recipes-extended/less/less_600.bb b/meta/recipes-extended/less/less_600.bb
index 9ebe39daab..f51083e1de 100644
--- a/meta/recipes-extended/less/less_600.bb
+++ b/meta/recipes-extended/less/less_600.bb
@@ -31,6 +31,7 @@ SRC_URI = "http://www.greenwoodsoftware.com/${BPN}/${BPN}-${PV}.tar.gz \
 SRC_URI[sha256sum] = "6633d6aa2b3cc717afb2c205778c7c42c4620f63b1d682f3d12c98af0be74d20"
 
 UPSTREAM_CHECK_URI = "http://www.greenwoodsoftware.com/less/download.html"
+UPSTREAM_VERSION_UNKNOWN = "1"
 
 inherit autotools update-alternatives