diff --git a/tests/gpgscm/scheme.c b/tests/gpgscm/scheme.c
index 4c28230f1..5f2f205da 100644
--- a/tests/gpgscm/scheme.c
+++ b/tests/gpgscm/scheme.c
@@ -1390,6 +1390,8 @@ static void finalize_cell(scheme *sc, pointer a) {
     if(a->_object._port->kind&port_file
        && a->_object._port->rep.stdio.closeit) {
       port_close(sc,a,port_input|port_output);
+    } else if (a->_object._port->kind & port_srfi6) {
+      sc->free(a->_object._port->rep.string.start);
     }
     sc->free(a->_object._port);
   } else if(is_foreign_object(a)) {