--- exim-4.69.org/src/daemon.c	2009-06-01 23:02:02.505119117 +0200
+++ exim-4.69/src/daemon.c	2009-06-01 23:09:58.088404461 +0200
@@ -25,7 +25,7 @@
 
 static smtp_slot empty_smtp_slot = { 0, NULL };
 
-
+static time_t sigalrm_seen_last;
 
 /*************************************************
 *               Local static variables           *
@@ -1603,6 +1603,8 @@
 
 smtp_input = TRUE;
 
+time(&sigalrm_seen_last);
+
 /* Enter the never-ending loop... */
 
 for (;;)
@@ -1753,6 +1753,8 @@
       {
       DEBUG(D_any) debug_printf("SIGALRM received\n");
 
+      time(&sigalrm_seen_last);
+
       /* Do a full queue run in a child process, if required, unless we already
       have enough queue runners on the go. If we are not running as root, a
       re-exec is required. */
@@ -1885,11 +1889,19 @@
 
   else
     {
+    int time_diff;
     struct timeval tv;
     tv.tv_sec = queue_interval;
     tv.tv_usec = 0;
     select(0, NULL, NULL, NULL, &tv);
     handle_ending_processes();
+
+    time_diff = (int)difftime(time(NULL), sigalrm_seen_last);
+    if ((queue_interval > 0) && (time_diff > (2*queue_interval)))
+      {
+        sigalrm_seen = TRUE;
+        log_write(0, LOG_MAIN|LOG_PANIC, "daemon: queue-runner not run for %lds. Forcing. Is SIGALRM delivery broken on this system ?", time_diff);
+      }
     }
 
   /* Re-enable the SIGCHLD handler if it has been run. It can't do it