diff --git a/contrib/buildrpm b/contrib/buildrpm
--- a/contrib/buildrpm
+++ b/contrib/buildrpm
@@ -11,7 +11,6 @@
 
 BUILD=1
 RPMBUILDDIR="$PWD/rpmbuild"
-export HGPLAIN=
 
 while [ "$1" ]; do
     case "$1" in
diff --git a/contrib/packagelib.sh b/contrib/packagelib.sh
--- a/contrib/packagelib.sh
+++ b/contrib/packagelib.sh
@@ -8,6 +8,9 @@
 #
 # node: the node|short hg was built from, or empty if built from a tag
 gethgversion() {
+    export HGRCPATH=
+    export HGPLAIN=
+
     make cleanbutpackages
     make local PURE=--pure
     HG="$PWD/hg"