diff --git a/src/mod_fastcgi.c b/src/mod_fastcgi.c
index 1a6ccb76..4c16b8d3 100644
--- a/src/mod_fastcgi.c
+++ b/src/mod_fastcgi.c
@@ -1424,7 +1424,7 @@ static int fcgi_establish_connection(server *srv, handler_ctx *hctx) {
 	} else {
 		fcgi_addr_in.sin_family = AF_INET;
 		if (0 == inet_aton(host->host->ptr, &(fcgi_addr_in.sin_addr))) {
-			log_error_write(srv, __FILE__, __LINE__, "sb", 
+			log_error_write(srv, __FILE__, __LINE__, "sbs", 
 					"converting IP-adress failed for", host->host, 
 					"\nBe sure to specify an IP address here");