diff --git a/src/libiso8601/build.install-lib b/src/libiso8601/build.install-lib
index ec04871..a8ade9a 100644
--- a/src/libiso8601/build.install-lib
+++ b/src/libiso8601/build.install-lib
@@ -22,7 +22,7 @@ install_header ${libiso8601_HEADER} ${INCLUDEDIR} 0644 || return 1
 
 # install config script
 echo "Installing config script into ${BINDIR}"
-CONFFILE="${BINDIR}/libiso8601-config"
+CONFFILE="${INSTALL_PREFIX}${BINDIR}/libiso8601-config"
 
 do_cmd rm -f "${CONFFILE}"
 do_cmd_redir "${CONFFILE}" sed \