diff --git a/util/postinstall.sh.in b/util/postinstall.sh.in
index 0ac59e04..c81a09ea 100755
--- a/util/postinstall.sh.in
+++ b/util/postinstall.sh.in
@@ -353,7 +353,7 @@ execute_post_install_tasks() {
    echo "Done."
 
    echo -n "Initializing sphinx indices... ";
-   su $PILERUSER -c "indexer --all"
+   su $PILERUSER -c "indexer --all --config $SPHINXCFG"
    echo "Done."