diff --git a/src/cfgparse.c b/src/cfgparse.c
index d01b4754a..2d226baf0 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -1638,6 +1638,11 @@ int cfg_parse_listen(const char *file, int linenum, char **args, int inv)
 					      file, linenum, *err, newsrv->id);
 					return -1;
 				}
+				if (val <= 0) {
+					Alert("parsing [%s:%d]: invalid value %d for argument '%s' of server %s.\n",
+					      file, linenum, val, args[cur_arg], newsrv->id);
+					return -1;
+				}
 				newsrv->inter = val;
 				cur_arg += 2;
 			}
@@ -1648,6 +1653,11 @@ int cfg_parse_listen(const char *file, int linenum, char **args, int inv)
 					      file, linenum, *err, newsrv->id);
 					return -1;
 				}
+				if (val <= 0) {
+					Alert("parsing [%s:%d]: invalid value %d for argument '%s' of server %s.\n",
+					      file, linenum, val, args[cur_arg], newsrv->id);
+					return -1;
+				}
 				newsrv->fastinter = val;
 				cur_arg += 2;
 			}
@@ -1658,6 +1668,11 @@ int cfg_parse_listen(const char *file, int linenum, char **args, int inv)
 					      file, linenum, *err, newsrv->id);
 					return -1;
 				}
+				if (val <= 0) {
+					Alert("parsing [%s:%d]: invalid value %d for argument '%s' of server %s.\n",
+					      file, linenum, val, args[cur_arg], newsrv->id);
+					return -1;
+				}
 				newsrv->downinter = val;
 				cur_arg += 2;
 			}
@@ -1704,6 +1719,11 @@ int cfg_parse_listen(const char *file, int linenum, char **args, int inv)
 					      file, linenum, *err, newsrv->id);
 					return -1;
 				}
+				if (val <= 0) {
+					Alert("parsing [%s:%d]: invalid value %d for argument '%s' of server %s.\n",
+					      file, linenum, val, args[cur_arg], newsrv->id);
+					return -1;
+				}
 				newsrv->slowstart = (val + 999) / 1000;
 				cur_arg += 2;
 			}
diff --git a/src/checks.c b/src/checks.c
index 82de26037..a0bca95ca 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -529,6 +529,7 @@ static int event_srv_chk_r(int fd)
 void process_chk(struct task *t, struct timeval *next)
 {
 	__label__ new_chk, out;
+	int attempts = 0;
 	struct server *s = t->context;
 	struct sockaddr_in sa;
 	int fd;
@@ -537,6 +538,14 @@ void process_chk(struct task *t, struct timeval *next)
 	//fprintf(stderr, "process_chk: task=%p\n", t);
 
  new_chk:
+	if (attempts++ > 0) {
+		/* we always fail to create a server, let's stop insisting... */
+		while (tv_isle(&t->expire, &now))
+			tv_ms_add(&t->expire, &t->expire, s->inter);
+		task_queue(t);	/* restore t to its place in the task list */
+		*next = t->expire;
+		goto out;
+	}
 	fd = s->curfd;
 	if (fd < 0) {   /* no check currently running */
 		//fprintf(stderr, "process_chk: 2\n");