diff --git a/src/http_ana.c b/src/http_ana.c
index 504f98a..a0507a3 100644
--- a/src/http_ana.c
+++ b/src/http_ana.c
@@ -4845,7 +4845,7 @@
 
 	/* <msg> is an HTX structure. So we copy it in the response's
 	 * channel */
-	if (msg) {
+	if (msg && !b_is_null(msg)) {
 		struct channel *chn = si_ic(si);
 		struct htx *htx;
 
@@ -4875,7 +4875,7 @@
 	/* <msg> is an HTX structure. So we copy it in the response's
 	 * channel */
 	/* FIXME: It is a problem for now if there is some outgoing data */
-	if (msg) {
+	if (msg && !b_is_null(msg)) {
 		struct channel *chn = &s->res;
 		struct htx *htx;